MJs have some of the best leafs ever (long, flexy and a good amount of arch), so your best bet for 8"s in the rear is a spring-over with a 3" Add-A-Leaf mixed in. Don't forget to think about a traction-bar too. The front is open to all sorts of possibilities, but if your goal is 37s, then it's highly advised that you search out a heavier-duty set of axles. My personal favorite would be a set from a solid-axle Ford F-250 (with the 8-bolt wheel pattern) as they are nice and strong (HD Dana-44 and a Dana-60) and it's a cinch to slice off the leaf pads and start from scratch for a new suspension. 8 inch kits are out there (remember that the front suspension is identical to the Cherokee) and if you can live with 35s, than your front axle can survive if you can control use of the happy pedal. You rear Dana 35 on the other hand, well, I'd look into an axle swap there. Either an MJ/XJ Dana-44 or the 95+ Ford 8.8 from a v8 Explorer. car-part.com may help track down some parts.
If you've got some fabbin' buddies, look into making a custom flatbed that ends at the rear shackles. You can integrate your rollbar/cage into it. I just read that fuel cells are not DOT-approved so you might want to stick with the original tank. Rocker protection is a must. Your best choice of engine will most likely be the 3.1/3.4L Chevy engines found in late 80s and early 90s Camaros and Firebirds. It bolts into your truck with only a couple minor adjustments and makes good power. You don't want too much power though if you plan on keeping the tranny and t-case. If the whole drivetrain can go, then the possibilities are limited only to how much cooling you can give the engine (the stock 86 radiator space is rather puny).
If I remember right, Texas lift laws only state that the headlights have to be below like 52" or something like that. Just be sure to add some removable big ol' mudflaps for on the street. It's a courtesy to others, and at the very least it makes it *look* like you care about legality. ;-)
You can check out the pics of my MJ project at the addy below. It's not as drastic as what you seem to be planning, but you might pick up some cool ideas. And don't forget to take lots of pics during the build-up so you can share it with the rest of the Jeepin' world!
Jeep on!
--Pete