Possibly selling my 96 classic to my sister so she can use the motor to replace the 94 4.2 that she has that is having oil pressure problems and she can't find parts to fix it with... I am not as well versed in the "Classic World" as I am with D90's and D1s so I am hoping to get some feed back on this.
This has nothing to do with the mechanical process as an engine swap isn't that hard. More about the electronics of a 94 classic vs what is on a 96 4.2. Would I absolutely have to swap the wiring harness and computer out with the 96 motor to put it in a 94 or would the 94 wiring harness support the new 96 4.2.
What would be the "challenge" of the swap? Any help is appreciated

 

I'm assuming you mean 95 as that was the last year of the classic and 96 was the p38 range rover.

95 to 94 both RRC should be a straight forward swap

 

Yes, You are correct. It is a 95. Ive never had it on the road so never paid much attention to the dates. Thanks for the info.
M

 

Because the '95 engine is serpentine and uses a different power steering pump and a/c compressor ( among a couple of other odd items) there will be differences between the wiring harnesses. As I'm thinking of all this, the a/c coolant lines are different, the a/c Condensor and fans are different, oil cooler lines are routed differently.