sorry to say guys but to tell you the honest truth if IH's were easier to come by i would drive those instead of Chevys my IH is one tough truck '68 1100C 4x4 long bed 304 V-8 4spd dana 44s front/back both with IH Powerlock Diffs (Posi) and it can take some abuse (just needs bigger tires, which i just bought on Fri Apr. 20) for IHs they had the 304, 345, 392 V-8s and alot of the parts between them are interchangeable if you get a 304 youre kinda stuck with the 2 barrel carb because the intake on the 304 is like an 1 1/2 in. narrower then the intakes on the 345 and 392 which did come with 4 barrels if you want info on your IH motor go to
www.binderbulletin.org theres lots of info on that site theres plenty of performace mods out there for IH motors but they are pricey i here there is 4 barrel intake for the 304 now but its like $500 but theres companies that make fuel injection kits, electronic ignition kits, and lots of other stuff
Nate