It's been 4 or 5 years since we used them, but Central Florida Avionics had some older avionics techs that were very familiar with Brittain. They brought mine back from the dead after I purchased my V35.
Way back in the late 90's, I had a V35 with a Brittain AP. Overhauled it and spent tons of money on it. I soon realized as most owners of that AP, that it's a worthless anchor in an airplane. I'd save your money for an AP upgrade to anything else.