Thanks, both are excellent ideas (dual electric fans and mod rad support). I did more careful measuring today, now that it's not raining, and came up with only a 5/8" difference. I think with dual fans and possibly cut the pump shaft and press the pulley back (LS Truck Water Pump Hack
https://www.youtube.com/watch?v=5YQNYiIvNDg), I should be able to squeeze it all in there. If not, the support mod is a good plan B.