I always get raked over the coals for suggesting to loosen the rear main to get the upper seal out but if you do this the seal comes right out with no turning of the crank.
With an auto trans - remove the converter bolts and push the converter back to disengage it from the crank.
Then loosen up the main caps - more at the rear and less at the front of the engine.
That may make things easier for you.
What I would do then is remove each cap one at a time and make sure the bearing shell tang is in place then install that cap and tighten.
Since you are turning the crank you don’t want to take a change that a shell rotated out of alignment.
