I stand corrected - Crutchfield claims there is 7.15" of usable space in the dash to install the stereo and the Empeg manual claims you need 6.8". You should be able to squeeze it in there.

I used this Tuffy console. Some online retailers claim that the 8" doesn't fit in the later YJ's and that you have to run the 6.5", but you can cram it in there and it works just fine. The extra lockable space is really nice to have. The price is a bit high, but I just watched Craigslist until one came available.