The site I listed is not a "write up" on the swap, it is an entire forum (just like jeep tech on this site) for swapping in the 4.0L engine into Jeeps. There are a bunch of YJ guys on the site that have done the swap and have posted enough information that you could do the it without ever posting a question.

As far as $$$. A properly built stroker is gonna cost in the thousands when it's all said and done.

If you're worried about power don't be. I heard all of those 258 (I too used to be one, even went with a 4.0 head on the 258 with a Weber Carb before the 4.0L) guys telling me how much I'll miss my low end torque; paaaleese. I can be sitting at a stop light, in the dry humid 80* weather (dry pavement), flip on my rear ARB locker, and power brake both rear 33" tires until the rubber runs out. The 4.0L provides plenty of power for most (un)modified rigs out there.

Chris