As many know one of the issues of putting a Magnum V8 into the Cherokee is that the radiator hose inlet and outlet are on the opposite sides between the I6 and the V8. After doing a little research I found that there are very few options for a radiator that will fit into the stock XJ location and work with the V8.
There is one company who makes a "custom" radiator (I forget who) but it was around $650. My other option would have been to run the hoses across the engine bay to the side of the radiator as required. The cross compartment hose option has been used by others and has worked out fairly well but I really didn't want to do that. My last option was to make what I had work some how.
The Radiator in my Jeep was essentially brand new as I had a problem with the idler bearing go bad and the fan went through the original radiator. Because of this I was a bit apprehensive about butchering the new radiator but I figured it was cheaper than a custom unit.
What I did was take a small pry bar (screw driver) and pried up all of the crimps on the radiator ends that hold the plastic tanks on. This was super easy though a bit scary as once you start your committed! Once the tanks were off it was just a matter of fabbing up some tanks and welding them on. In addition though you need some hose inlet/outlets, a weld in fitting for the drain, and a cap inlet. I bought all of the aluminum fittings and inlets from Speedway.
Another issue is you need a way to weld everything together. Buying a TIG welder, though nice, would sort of defeat the purpose. I already have a really nice Millermatic 210 but of course that won't work for aluminum. A spool gun was in order. The problem is, the spool gun required for the 210 is around $650, again defeating the purpose. Miller makes an inexpensive gun, the Spoolmate 100, but the local dealer told me it wouldn't work because the welder I have is "all wrong" for the 100. Hobart makes the same version of the gun (Miller owns Hobart) and they call it the DP3035-10. Seeing as the gun Miller recommends for the MM210 is the Miller 3035 I figured the guns were very similar. It turns out that the Hobart gun is in fact the same as the Spoolmate 100.
The only problem with the Hobart gun was the part that goes into the welder is too small. It took the machinist at work about 1/2 hour to make me an adapter and I'm happy to say the gun works stellar! MIG welding aluminum with a spool gun doesn't turn out stack of dimes welds like a TIG but with some practice they're perfectly acceptable and plenty strong.
So with a $200 spool gun (plus $80 for an argon tank) plus about $100 in aluminum and fittings I have a custom radiator with the inlets and outlets on the correct side. Of course the bonus is I now have the provisions needed to weld aluminum!
Here are some pictures of the final product. I still need to pressure test it but any leaks should be pretty easy to plug.
P.S. I used 1/8" aluminum for the tanks. I tried to bend it at home in a vice and FORGET it. I had to take it to work and bend them an a brake, so you either need to use thinner or softer stuff (I used 5XXX).