well hang on here it a hemi and it would have a flex plat and the ring gear on the converter so your hub could be thicker or thinner would have to do with how much the crank hub hangs out of the block if you know how thick your adapter is to bolt up the trans and you know how thick your hub spacer is subtract to two that will give you how much spacing you have and if you have a chevy V8 engine and measure a chevy from hub to bell housing face it should come out the same as you hub? or just PM me and i will tell you if you want to call me on the phone