its specifically the spider gears you're talking about. I don't have pics handy, but you want to look into the axle holes, and make sure you see 4 gears, all facing inward.
imagine this with a tranny case over it, and without the pin in the middle:
also - it doesnt have to be a socket.. i typically use rope or wire - whatever will keep 1 gear tightly in place (this will keep all of them in place)
imagine this with a tranny case over it, and without the pin in the middle:

also - it doesnt have to be a socket.. i typically use rope or wire - whatever will keep 1 gear tightly in place (this will keep all of them in place)