I ended up running a smaller than optimum raidator, but I hedged my bets by making it aluminum, and hooking it up to a good fan with a great controller. So far, so good -- I started withg a standard core that almost fit the space in front of the bulkhead under the upper lip and above the welded in support horns at the bottom of the bulkhead, then had the radiator outer tanks modified to better fit the space. The result looks good and fits well.

Depending on who you talk to, aluminum radiators are 20-25% more efficient than a standard brass radiator. Keep in mind that the cores are differnet dimensions, as well, and that one aluminum core is generally as deep as two standard cores, and the aluminum cores flow better, as well.

Randii