Thick.. or thin?

[stockk5]

I have a 14bolt that was a bolt in to my k5. I bought it off some guy, it came with a detriot and 4:56gears. i am unsure if the gears are thick or thin, i need to completely rebuild the rear end, and ready to order gears, i am unsure if they are thick or thin, how do i tell? any numbers? measurements? thanks guys!

 

[nvrenuf]

Look at the side of the ring gear for part number info stamped in it. If you find "GM" next to an 8 digit number it should be the OE part number which indicates a "thin" style of gear.