The engine will fit. The Getrag assembly is about 1.125 inches shorter to the cross member and the starter is different and is clocked to the adapter differently. There may be issues with frame clearance. The rear is also shorter but I don't remember by how much, .75 inch on each side if my memory serves me. The wheel studs are different size also. I know newer D80,s and AAM rears have been swapped into 1st gens so it could be done the other way too but not a bolt in. The biggest hurdle would be the starter to frame interference and the length of the Trans to crossmember.

However having said that you could use the adapter, starter and trans from the 2nd gen on the VE pumped engine.