I would let the ARC do it if you are going to replace the input tubes as well. Output tubes are easy to replace and bias, but those input tube biasing is not easy.
If you are going to buy all those (perfectly) matched tubes, it will cost $400 anyway. If you send it to ARC, they will not only do it correctly but also check all the other specs and do the necessary maintenance.
If you are going to buy all those (perfectly) matched tubes, it will cost $400 anyway. If you send it to ARC, they will not only do it correctly but also check all the other specs and do the necessary maintenance.