Honestly, whatever came with the shifter should go on the shifter. IMO. Its like taking something apart only to put it back together and find some screws left over....."the jobs done, but uh, where the hell should these go"..............its not a good feeling. You never know, something may break in the future. Take the time to put those washers on ASAP......as far as 90% shorter throws, I doubt that, i've seen up to 45% tops on some top of the line shifters, but never 90%.....then again I could be wrong.