The oil drainbacks at the bottom corners of the hemi heads obviously won't line up w/ the wedge block. You could plug them from the bottom of the head and then drill and tap it from the side for an AN fitting and run hoses down to the pan like on a B1 head.

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax