Oil leak from between the right head and intake

It is possible someone did not put sealant on the intake bolts. The bolt holes go all the way through the heads into the valve cover area. If left unsealed, oil will defy gravity and migrate UP the bolts and leak out onto the intake. Either way, it sounds like you may have to remove the intake to repair it and if you do, don't forget sealant on the bolts. I like Permatex #2, but any high quality sealant will work.

Also, if you do remove the intake, do NOT use the cork OR rubber end gaskets as they harden over time and leak. Look and see if the intake locating pins are still in the block on either end of the intake valley. If they are remove them. Then when you go back with the intake manifold, put a bead about 3/8 of an inch thick along the block ends where the intake meets the block. Also connect the beads to the intake gaskets in all four of the corners where the heads meet the intake.

Lastly, you will need to coat the water passages of the intake gasket with sealant on BOTH sides of the gasket, so you will be sure the water passages are sealed good.

Don't forget, torque on aluminum intake manifolds is mild. 20 LB FT is all you need.