The hemi is physically large and quite a bit heavier than an lt engine and lower tech. It might integrate easier, cooling would be more challenging also with minimal real estate under the hood. I would hate to ruin my jeep with any poor conversion. Lots to think about with any of these 8 cylinder conversions.This one is by far the most credible source on the cost of a hemi swap:
JK gear and gadgets - My Jeep Wrangler DIY hemi seap cost how much?
If you haven't watched that yet, do it now.