When I installed my ZSpeed bracket, it was plug and play. No measurements of anything, I simply bolted it in with no issues. I have a stock driveshaft and shifter however... Do you have OEM teflon shifter bushings? I upgraded to bronze ones during my initial install and was really disappointed. After going back to OEM teflon bushings, I heard angels since when shifting with the ZSpeed bracket. Perhaps it has to do with trans mount? It is so strange that some people have a world of trouble with these, while others do not.