and we'll need to know what a "small block 266" is as well - we know the dimensions of a 283, 327, 350, but a 266 is a whole new concept - also has it been clipped? is the rad mount original? what driveline you using?
OTOH you could try having the cab, rad and driveline set in place, and it should be pretty simple to see if it all fits!
Bill
