Helping a friend out on his 50 Buick working on the drive shaft to replace the seals. First time were doing this and doing it by the seat of our pants and tips here and there from people. He got the the parts we need. What were not sure of is the shims are color coded. What do the colors stand for? It's the one thing were stumped on and don't want to put this together and have to do it all over again. Thanks for the help.