drill some new holes..
its an easy swap and lots of folks here have done it.. I grafted a yj tub onto a cj frame.. then i broke the cj frame and put that body on a tj frame... they are all pretty close..
there MAY be an issue with the front clip being too high when you use a cj front clip with the yj frame.. some folks say its an issue, some dont.. its easily fixed with a very mild body lift either way.
I don't know about the "mild" body lift thing. I had to go 3 inch before my radiator would clear the steering gear. (of course the driver's side front tub mount is saggin' some, so I prolly coulda gotten away with 2 if the rest had been right... [img]images/icons/frown.gif[/img]
Otherwise Elusive's right... It's really pretty simple if you take your time. The other main thing to be aware of is the gas filler tube difference (cj's are on the other side from the Yjs) so you may have to do some creative plumbing. [img]images/icons/wink.gif[/img]