As appears in another post, if you're willing to sacrifice your original fuel pump drive (in "favor" of an electric fuel pump), a full-time cartridge oil filter can be adapted to the engine without machine work to the block. The steel line between the oil pump's high pressure outlet and the main bearing bulkhead are interrupted, lengthened, and passed out through the pump drive opening to the filter, then back again.
I wrote up some of the work, if anyone is interested e-mail me.
