Hey Scotty, Im a newbie at pepperoni and I just used my meat grinder for stuffing pepperoni yesterday, and I got the same results as you. The meat was so pale looking, I would have sworn it was sick.
A short while in my smoker and the great look of pepperoni was right back. The flavor that I had hoped to achieve is there, but like you mentioned, the texture of the meat isn't what I want.
I have 10 # of pepperonie meat all mixed and its been in the fridge for 2 days, I will go ahead and stuff it now with the meat grinder / stuffer, but I don't plan to do anymore stuffing with the grinder.
I have a Dakota watere stuffer ordered and will wait for it to get here before I do anymore stuffing.
BTW Yours look awesome. I'm sure they taste as good as they look.