Yes, sump, pickup etc will all fit. Any HJ onwards 308, 304 or 350 that is TH pattern can be redrilled for 4spd/trimatic pattern. The only ones you can't redrill are HT-HQ from 4spd/tri to TH.
The only major worry is technically you can't use that bottom end in an early car without fitting all the injection and the standard memcal - you are supposed to have all the same emissions equipment as the car that donated the engine. In a HG this would also mean a sealed fuel tank, vapour separation, canister etc. If the car is already registered you'll have no dramas probably, it'd probably only ever come up if you got defected or had the EPA hassle you. The date codes on the 1994 to early 1996 VR-VS blocks are the best ones as they are consistent with 1974-1976 date codes eg 24H5. The rest are not as they are not in the US format as per 1969-1973 308 or they fall into the late 70's pollution era. The later VR and VS blocks are good too as there is no 5.0L on the sides, they are blank as they blocks were used in both 304ci and 350ci applications.

If you are going to use red heads the in-valley head bolts aren't used, just use good gaskets. If you are going to use the bottom end as is with original VS pistons, cam etc and the EFI heads with a carby make sure you use a dual plane manifold. I did this with my Overlander, put a VP SS 5.0L long engine in it with Redline Hi-winder single plane, 600 Holley, HEI dizzy and LPG. It was doughy as hell on both petrol and LPG. A combination of low compression, the original EFI cam, big port heads and single plane manifold. It was only a stop gap measure as I intended to fit the EFI back on later, just had to get it going in a hurry as the 308 was dying.