2002 GMC Yukon Starter on 2002 GMC Yukon

For the past couple of months, I have had an intermittent problem. The Yukon would not start. Battery seemed good, but I would try to jump it and after a few minutes it would start. But not right away which makes me think it wasn't the battery. And it would occur when the battery shouldn't be dead. Such as after I fill up gas. Anyways, I replaced the battery with a brand new one and I still had the same intermittent problem. The other day, it wouldn't start at all. Same symptoms.

All electrical turns on inside the car. The starter relay clicks, but it does nothing. If I hold the key in the start position for a few seconds, I hear a crack in the speakers. I've tried a new battery and to jump start it, but absolutely nothing. No cranking.

I'm assuming it is the starter but don't know how to get to the wires on the solenoid to check voltage without removing the starter. The solenoid is on top of the starter and I can't get to it from underneath and don't see it from the top. I tried to remove the starter, removed the 2 bolts and the plastic cover, but couldn't get it to move enough to get it to drop from the transmission. I gave up and put everything back.

I also see a 2-pin connector just hanging about 8" off of the positive battery block (red plastic box) but can't see anywhere that it might go. I've tried looking at other Yukons but haven't found someone with the same year as mine.

Would a starter problem start with intermittent problems? Can you please provide specific guidance on where the wires on the solenoid are to check the voltage? Any other ideas?