Have a 91 350 auto/air supposedly with HD cooling, and today found radiator to be the 3 core style (19x28 1/4).. Radiator.com has a replacement for $149 (cheap enough I guess), but i'm wondering what it takes to go to a 4 core? (both installation & price) LMC catalog lists a 4 core, but.. doesnt' have different support brackets for different 'row counts'. ANyone been down this path latley? Advise? I'm going to be towing with this more frequently (now the the 4:10s are in it!), so the 4 row is definately preferred! THinking of an elec fan as well (heck, there's room inside the shroud!) Thanks!