You can have a machine shop drill rotors, ream knuckles, and weld up your spacer. The hardest part was changing the ball joints. You have to weld up your drag link and tierod. If you can do thoes things everything else is just putting things together. It is well worth doing just for the brakes.
Search for frankz's write up, this is what I based mine off of.
wj knuckles (2004)
spacer for knuckle
wj front rotors (redrilled to 4.5)
wj akebono callipers (2004)
wj ball joints
unit bearings (2000 xj)
brake pads (2004 wj)
bolts to mount callipers to knuckles
drag link
tierod
high steer trackbar bracket
re/build trackbar
16" rims or 1.5" wheel spacers
4 washers to space calliper from knuckle so that the rotor is centered in the calliper.
When I did mine I did a TnT Truss w/trackbar bracket and upper mounts, TnT coil buckets. Ballistic fab lower control arm mounts. Blazer tierod ends ("Chevy 1 Ton") 1.5"x.25" DOM for Draglink and Tierod. Summit Racing drilled slotted rotors (wj front/explorer rear) and greenstuff brake pads. It works good and stops great!!
It was a week project for me, a few hours every day. Cut off old hardware mocked up new. Replaced balljoints, a pain in the @ss. Mounted knuckles, back under jeep. Burnt home new brackets. Mounted brakes, measured for tierod/draglink. Made tierod draglink, mounted. Rebuild trackbar, mounted. Put spacer on, put tires on, driveway alignment, test drive. Get passengers nose to touch dash with new brakes on 35's priceless.