07 suburban 5.3L, 215k, Trans is a 4L60E

Dirty work is done... I removed 3 Flywheel to converter bolts (if there is a 4th please let me know). I also have removed a total of 8 bolts/studs around the Bell Housing and there is no sign of separation at all. Is this common for older high mileage vehicles? Anything I am missing or a technique that works well??

Really need help before I bust something.

Thanks

 

I had similar issue, make sure all grounds are off, had one I missed passenger side low on block near fly when. Used a 5 foot spud bar under motor mounts one side at a time moving it 2 inches up and down.
Finally broke lose. Be careful to leave torque conv. Stays in when she comes lose.
Other than that I would say may have a stud still in even though nut cane off. Some studs have two nuts on each of the post. Good luck man don't bust anything! Walk away take a break