i have a 258 out of an 81 or 82(not really sure) AMC eagle in my 79 with QT. it was a complete drop in. CJs have the th400 with the amc bolt pattern so it should bolt right up. i am unsure bout the mounts. i may be completely wrong but i believe they changed mounts in 87 but i think that was only cause of the wrangler frame. the mounting points on the block should(?) be the same. so when you pull your engine, pull the mounts offa it. is the engine coming from a 4wd? remember to pull the pilot bushing. when swapping a 300 ford from a 4wd truck to an automatic van, i spent hours trying to figure out why they wouldnt mate up. i dont know if 258s are the same though. good luck.
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