I have a used set of old Shimano XT cranks that will allow me to use a 46-30 chainring combo. I will use them on an older rando frame. Are there companies in Northern Ca. that could lightly refinish an old set of aluminum cranks?
Thanks, Don

Don,
There's really no re-finishing old anodized cranks. Well, you could remove the old anodizing and re-do it but I think you'd find the cost prohibitive.
Two choices; clean them up best you can and use them. Or, remove the anodizing with oven cleaner and polish them up using aluminum polish or something similar. They will, of course, oxidize with their protective coating removed so you'd have to clean and polish them from time to time.

I've found that a good coat of wax will really slow that down. The cleaner wax I use even lightly polishes so I use it as the final step on everything I mirror-polish.

Check a local for anodizer/plater. Lots of them do powder coat finishes now that are very thin and would work well for those cranks. Should be cheaper than anodizing which can sometimes have a large minimum per job.