Are you using stock main cap bolts or studs now?
I use a adhesive silicone(it must have adhesive on the label ) to stop leaks on the main seals on BB by filling in the sides of the cap between the block and seal holder, both sides facing the flex plate, flywheel and also on the bottom, top of the seal holder, touching the block
I use a flat thin putty knife or small flat thin blade screw driver to force it into the hollow spots all the way all the way around the seal holder, take your time to get it correct
I also use a tiny dab on the seal half ends where they butt up against each other, I don't stagger them either I use a little tiny bit on the cap to the block surface also, not a bunch
I can't remember the last time I had a rear main seal leak, probably over 40 motors ago I can't say the same thing about the rear cam plug I seal them up now also with the adhesive silicone after they are installed all the way into the stop groove step
IHTHs