does any one know where i could find out how other people did it

I did it on my brothers XJ. I'll try to take some pics of it this weekend....

check out naxja.org tons of info there

I did a write-up and with pics for our local site that never got published so I put it on my site (http://www.tcinternet.net/USERS/JKORDA/jeep/mods/tjflares.html).

Pics of my XJ with TJ flares (http://community.webshots.com/album/199773370yCuCxX)

I shaved the backs flat and notched the bottom ends to fit around the body. Fronts are bolted on and the rears are on with self tappers.

TJ to YJ,XJ,ZJ
http://www.links4jeeps.com/search.php?whichtype=all&filled=1&search=flares

http://i22.photobucket.com/albums/b328/crapxj/tjflareinfo2.jpg there are opening where the body seem comes apart. could i hammer those shut or should i weld some sheet metal in there?

Thats the rear pinch seam. That needs to be welded shut, or the unibody will lose structural integredy.