need conversion info

i need to know if the guts from a 88 d35 rear will fit in a 93 d35 out of a grand and if the np231 out of the 88xj can be converted to work in place of the one in the grand i am not sure of the xact t-case in it atm

How much of the guts? The '88 XJ D35 is a non c-clip axle, a '93 ZJ D35 is a c-clip axle. The ring and pinion gears will interchange, but I think the spider gears are different, to accomodate the c-clips. I know the axle shafts are different.

'88 XJ probably has a 21-spline transfer case. '93 ZJ should have a 23-spline.