A few years back one of the Stockers I spoke with (I think from AZ) was even using a stock shortblock! Just cranked down the wastegate
The one that was in my 81 had head studs and supposedly an Ultradyne cam. They had alos put on a Holley 3310 instead of the Qjet. The biggest issue I see is the crazy intake ports! Siamesed for two cyllinders and a pretty narrow cross section .
I would think a TB EFI might be a good choice also.