1990 Nissan Maxima Unable seperate tranmission from engine

Transmission problem
1990 Nissan Maxima 6 cyl Two Wheel Drive Automatic 170.00 miles

Hi, I could not separate automatic tranmiission from engine, Nissan maxima 170.000 miles, all the bolts attaching to engine have been removed and 4 bolts attached driveplate to torque converter have been removed, too, and two rear tranmission holding have removed, and all hardness connection have removed.
I see the case seperated the engine about 1/2 to 3/4 inch, but the torque converter didi not seperate from driveplate, 4 bolts have been removed, even how hard I pulled and lower, but It didi not complete seperate.
Please, someone tell me what did I do wrong? Can on Nissan Maxima 1990 tranaxle remove from engine as seperate unit? Any helps will be appreciated