I am interested in the TA33 upgrade on my 84 hot air. Prices are about the same within $50 or so. Deadbolt Enterprises is one rebuilder who talks good to me. I know there are at least 2 or 3 other rebuilders out there. PLEASE someone who has actually had the upgrade done tell me who did it and how happy they are? Also several of you please give your input as I don't need to make a $850 mistake... THANKS...mike