If you are going to make it out of 1.25" tubing, I think maybe it should all be the same size. If you do drop down a size for the crossbars, I would only drop to 1". Just my opinion since nobody else chimed in!
A drop in size to 3/4 would be a large difference and might look kinda small in comparison. whatever size you use, just go for it! Make sure to take lots of pics during fabrication so we can all see what you're up to!
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02 Red KJ Sport,33s,
custom fenders,custom roof rack,custom 5" susp, cradle drop,
V8 swap[url=http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=68&t=64049]04 KJ, 4" Fox coilovers, Bilstein, 33's, RL front bumper
'05 WK Limited, Hers