you'll have a cat. in the 82 so you can take off the smog stuff, uhh... maybe a few wiring things (nick-nacks) but that should be it, but our little living dictionary (no offense 800xl) should have more info. on this.
just saw your post in the classifieds, is the 4x4 truck in the ad the same one your dropping the 81' motor in, then no, it won't work cause the starter on the diesel is on the driver's side and the starter on the gas motor is on the pass. side... the trannies would have to be swapped too in order for it to work.
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-Old ride-82 Luv diesel 5spd with some upgrades
-Past rides-82 Sierra, 78 Coupe De'Ville, 91 2dr Blazer, 86 RX7, 86 Porsche 944T (rear-ended and totaled)
-Curr. rides- 1970 Ford LTD 4dr, 390 4Bbl, 2nd owner! With a few Extras

00' Civic beater...