I went through this a few weeks ago in my 05 LJ with manual trans. Seems the PO had a chinesium radiator put in there and it decided that being a steam kettle would be a career move for it. Looked around and what few Mopars radiators I could find were out of my price range. I was also hearing about aluminum radiators and cracks after a year or two. I ended up with a CSF brass/copper radiator for an auto trans TJ. CSF says it fits YJs and TJs up to an 02, but there were no changes in TJ radiators from then to 06. so I got it. Bolted right up and I put a couple of vacuum hose caps over the trans cooler tube adapters to seal them up in case I get a wild hair to use that cooler for something like engine oil or power steering fluid.
The only mounting difference between the old radiator and the new is the bolt holes for the new one are 6mm instead of 1/4-20. I had some leftover 12-24 self tapping torx screws from another project and those worked great on bolting down the fan shroud.
So far though, I'm very satisfied with the brass/copper radiator.