Marc,
The ****** cooler I have on my liberty is just an aftermarket tube and fin type about 9"x5" mounted in front of the radiator on the driver's side. It has hose barb fittings. These are available from flex-a-lite, or b&m, etc. Mine was installed because the factory cooler (which is part of the A/C condenser) started leaking. My A/C works just fine, so instead of replacing a 300.00 part, I put in a <50.00 ****** cooler! It was a quick fix type thing...
If you're doing some heavy towing, you might want to go a little bigger even? And get a transmission temp gauge.
Also, the lines from the transmission to the cooler often develop leaks where they go from rigid tubing to rubber hose. I will eventually replace mine with braided stainless, from the ******, to a better cooler (like B&M) with threaded fittings. Then, it'll be a lifetime repair/upgrade.
Regarding the timing belt job. There are some reasonable kits on ebay, and other sources that have everything BUT the tool that holds the cam gears. I did mine without the gear holding tool, but I've done a lot of DOHC timing belts, and managed to pull it off. I wouldn't recommend doing it without the proper tools.
Mike