Hemi fitment issues in 68 dart?

OP has a Mopar block so there is an inlet for the external oiling on the front of the block. Using that inlet allows the use of a normal HV pump so you gain some space that way. Best way to do it is to have a good fab guy build a hard line that brings the oil from the pan up to the front of the block. It might cost a few hundred bucks to get the special line fabbed up but it would save a lot of space.