I have an SM465 from a 78 K20 that I plan on swapping into my 88 K5 which currently has a 700R4 and an NP208. I plan on keeping the NP208. I know the output shaft on the SM465 and the input on the NP208 are different, I have everything I need to do the swap except a coupler for the shafts. I believe Summit has one here. Does anyone have any experience with this situation?