Larry, FWIW IIRC the small block V8 Dodge (318 etc) operates at a 59 degree angle (measured from where I don't know). I expect that the I-6 having longer pushrods would have some effect due to pushrod flex but I expect that the angle change you describe would not be that drastic, special (custom) rocker arms could help with this if necessary (using small block Chevy wherever possible seems to be the cheapest).
