I've never seen that done - swapping a TJ body/front clip onto a CJ. I've seen the opposite - CJ front clip onto a TJ. Usually the goal is get the classic look (CJ) with the new amenities, e.g. rust-free, fuel injected, disc brakes... No clue on value.
1981 CJ8, Chevy 5.7, SM465, D300, RE 4.5, 35" BFG MTs, 20/30 4.56, Detroits, Warn 9500ti