I have been running 4:56 gears in the car. i am going to a bigger motor now, and want to run 4:10 gears in the car. Was told that they are two different cases, and that I would have to install a spacer to run the 4:10's My question is this true? does the spacer take away from the strength? Does anyone make a 4:10 gear that will bolt in without the spacer? I do run a spool. thanks.....