The trick with RTV (Oil-proof sealant) is to apply it to both surfaces to be sealed thinly and then assemble the parts but don't tighten them down fully as the sealant needs contact with the air to cure. Fully tightening before it has set will simply squeeze the sealant out of the joints.
After a few hours the sealant will have set sufficently for you to tighten the bolts to the correct torque setting.
I'm gonna be doing mine soon too, leaking is the last reason though. Gonna be fitting the ARP heavy duty rod bolts. Got a new uncracked sump from animal, just need some sealant and new gaskets. I suspect mine is leaking because i used haematite red to seal the two grooves in the end cap, and the gasket itself. I followed haynes and only applied sealant to the block face and the other side of the baffle (so basically the top gasket)