Mounting a 66 c20 cab to 71 c10 frame question

[LinkbeltOE]

I have a 66 c20 cab I want to mount to a 71 c10 frame and I don't know what kit from LMC to order. Do I order the 66 truck kit because of the cab? Or do I order the 71 kit because of the frame? Has anyone done this, if so what did you do? I don't want to order both and return the other to LMC but if I have to then I have to. I found out that you just can't mount a 66 core support the a 71 frame because the 71 frame nose dips down 3.75" from the top of the frame and the 66 dips 2.5" so before I make a mistake and build my fan shroud incorrectly I guess I better mock up the rusty cab on my powder coated frame first eventhough I'm not ready, thus my question. Any help would be much appreciated. Thank you in advance.