Because the TFI distributor has a longer shaft than the Duraspark type, if you use an early or heavy duty oil pump drive, the TFI distributor will not fully seat. Use the later model EFI oil pump shaft (5.8 only), I believe that works with either distributor type (it has a longer hex section).
I know, I found out the hard way. And, there is no changing the oil pump shaft once the motor is installed (provided you used the anti-pull out clip).
i just need to know what efi dist will work? cuz i bought this motor and it was carbed and im changing it to efi so i need a different one, it came with a msd billet one.