Dunno who Mr Cab is, but I'll give it a stab. On a small block you can install a copper tube in the pass side oil galley. The galley has to be opened up with a drill and the threads re-cut for any screw in plugs. A rounded over lifter is driven thru the lifter bores, peening them in so the lifter will fit. Then the passages from the galley to the oil pump and to the crank are opened thru the copper tube with long drills.
Find a copy of an MP Engines modification manual. They describe how to do this in that book.
Can this mod be done on a big block?