I also anodized my Cleveland 30-9 brake caliper.
With mixed success.
See my project at
https://sites.google.com/site/threeu...-brake/caliper

Bumper, I think the guy you are referring to is Joe or Jack Way at Sierra Specialty Automotive in Quincy, Ca.
http://www.brakecylinder.com/contact.htm
indeed, he retired, as the webpage says.

I was in touch with him 3 years ago for a brass sleeve job on my caliper, but he indicated that he had stopped doing aviation stuff for liability reasons.
If I recall well, he had some sleeves pushed out.
(Learning: tell your shop it is for a cart or something like that)

My anodizing job (done at a local shop) was not as successful as I had hoped for. I think the problem was in the severe pitting.
The anodizing does not fill in the pitting.
As is visible in the images, both the caliper and the piston were pitted where the O-ring sits.
I tried to polish that out, but could not get in deep enough.
Now, in very hot weather (100 F) the caliper leaks a bit.
I thinks the DOT4 gets so thin that it creeps through the pitting past the O-ring.

My suggestion: If you are looking to anodize your brake system and your aluminum is corroded, take care of the pitting first before you do the anodizing.

3U