What you stated would be "ideal," however not a requirement for a "fun project." My rig, when it was a 4banger, had plenty of go juice for offroad. It just didn't have the guts to make it up highway hills. I drive 25 miles each way.....highway. And it had 35's. A fourbanger is fine for a trail/city rig. Yes, 91+ is what you would want for fuel injected models. A fourbanger with 33's and 4.88 gears would get you in enough fun to satisfy most weekend warriors. Hard top/soft top makes no difference. Hard top is nice for winter, but more a pain for summer. The only downfall to soft tops is rain and wind. By nature, soft tops don't leak while driving....only when sitting in the rain. And if properly aligned, can be avoided. Your biggest enemy on a jeep.......rust. I would take a poorly running jeep with no rust over an overhauled jeep with the floorboards weakening from rust. Usually what you can see, is only half your problems when it comes to rust.
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