1993 Ford Thunderbird Loss of power

I’ve had this Thunderbird for aprox. Eight years and have had pretty good luck with it. The usual Ford electrical problems, mostly the headlight switch repeatedly burning out. I started having problems about a month ago. I’ll start from the beginning-
On my commute home from work, which is about 25 miles I noticed the temp. Gauge higher than normal. This happens if I forget to top off the radiator on the first of each month. It doesn’t take much coolant loss for this to happen. As little as a 1/3 gal. The car seems to burn a quart of oil between 3000m changes I immediately parked the car and waited for it to cool off some. I carry coolant in the trunk. I left the ignition on (engine off) to watch the gauge and after about a half hour when the needle went completely to the left was going to start the car and then top off the radiator. When I went to start the car the battery was drained and it would not turn over. Probably from leaving the ignition on. I called AAA and when the technician came he could not jump the car with the battery pack. He hooked the cables from the dual battery diesel tow truck and we waited a bit. He looked at the battery and asked how old it was. I told him I’ve had the car eight years and never had to replace the battery. He couldn’t believe it. “You need a new battery “I guess that says something for those Sears Diehard’s. After five minutes the car did start and I immediately drove it to Nationwise and they installed a new battery. When we were putting in the new battery we noticed that it was considerably larger than the old battery. The battery that was in the car was for a smaller vehicle. Not the one designed for that car.
Two weeks went by and the headlight switch burned out again. You had to push it in slightly for the lights to go on. I had a backup switch in the glove compartment and
have gotten to the point to be able to replace it myself. When I put the new switch in you
Still had to push it in slightly for the lights to go on? After a couple of days the driver side tail light bulb blew and I also replaced it.
A week went by and on my commute home from work I was driving the car a little faster than normally. 65mph compared to my usual 50mph. The car started losing power and when I tried to accelerate it wouldn’t go any faster. Also there was a burning smell. To me it smelled like an oil or maybe transmission fluid. I immediately pulled off and shut the car off. When I popped the hood some smoke came out from each side. When I opened the door some smoke was coming from under the door. I inspected under the hood looked under the car but couldn’t see anything. A half hour went by and I started the car and drove it the rest of the way home at 45mph without a problem. I thought it was a transmission problem and that morning took it to A & A Transmissions. They did a 15 point diagnostic test, drove it and said that it was shifting properly.
We decided to go ahead and service it and I brought it back the following day. The receipt says flushed, new filter, new fluid, and Ludeguard IS1, no leaks. One point about the transmission is that when the weather drops below 40’F, on the first start of the day it takes 3 to 5 seconds for the car to engage, reverse works fine. It’s done this ever since I relocated to the Carolina’s from S. Florida. Disappears in the summer but returns with the winter. A couple of days later on my commute to work (10:30pm at night) I again experienced the loss of power and the burning smell (only slightly). When I drove it home in the morning it was fine no problem. That night on my way to work it happened again more severely this time. I had the Security Guard smell the car he thought it smelled electrical. Each time I turned the ignition switch to the first position there was a humming sound coming from behind my head, drivers side. It always did this when starting but lately I’ve been hearing it while driving, repeatedly. While sniffing around the car and under the hood the smell seemed strongest near the battery. I brought it to the mechanic that morning (Precision Tune) there were no problems during the trip, twice my work commute but at 45mph.
I left the car with them. The mechanic and owner of the of the garage looked at it. They replaced the headlight pigtail (burnt). Right front high beam pit tail and socket. Multi function switch had a short ($285.00 Ouch!) And the passenger side tail light bulb. They found improper installation of wires to headlights, something that was done by a previous owner. I was advised and approved the services & maintence. They were unable to duplicate the loss of power condition or smell. They let the car idle for an hour with the
headlights on and nothing happened. When I picked up the car I was given the old parts and the mechanic showed the burns from the shorts. I said a prayer and hoped that the problems were solved.
On the way home I turned on the lights to test everything. About halfway home of what is probably a 30m trip I started to smell that smell again and the car was not accelerating properly. I turned off the lights and the smell stopped. The car continued not to accelerate properly. When I pulled into the driveway and got out of the car there was a humming sound coming from the exhaust pipes (buzzing). I pushed on the gas peddle a couple of times while in idle and the humming continued. I shut the car off and went inside. Six
hours later I started the car and heard a grinding noise for about 10sec. Then drove it to work the lights worked fine. I didn’t smell that smell. Although I did about 40mph the whole way, scared. I didn’t push the acceleration. I didn’t hear any buzzing from the exhaust. I’ll see what it does on the way home?
I’ve done a lot of research on the internet about the problem and have read everything from a bad universal joint between the engine and tranny. To a clogged exhaust system (catalytic converter). I even went so far as purchasing a fire extinguisher in case I have to deal with an electrical fire on the road. I wish we could pinpoint the problem!
It’s driving me crazy!