Wiring should be simple.  At worst case you'll have to move a couple
pins on the round white connector inside the black box, but check
Bentley to make sure.  You need to drill a hole for the ecu cable if
mounting under the rear seat.

Fuel pump eclectric will be 2 wires on late harnesses, no problem,
just hook positive to existing fuel pump wire.

Use a late model instrument cluster for oil pressure warnings/tach etc.
(swap pins on white connector if necessary)

I think your hardest bit will be changing over all the 2.1 cooling
system plumbing bits into your engine bay.

>I am contemplating swapping in a fresh 2.1 wbx in place of a failed
>1.9 in a 85 GL.
>I have numerous late model 2.1 engine bay harnesses and ecus.
>Is this a plug and play type swap or is the older wiring from the
>ignition and front of van not capable of the swap?
>
>TIA,
>
>dylan