Yes, now you've got it. ANY seven speed Shimano/SRAM Hyperglide cassette will work on your wheel regardless of # of teeth. Definitely replace the chain too. Any 6/7/8 speed chain will work fine.
Originally Posted by
Bill Kapaun
I actually don't know if all 7 speed bodies are "C".
Not all 7 speed bodies are compact. I've had non-compact 7 speed bodies and also Hyperglide/Uniglide compatible bodies with the threading for the last cog. I even have an 8 speed (Ultegra) Freehub body with the Uniglide threading.