Just a couple of comments about retubing a Mkiii. It uses 6H30 tubes not 6922's. The 6H30's don't need to be adjusted like the 6922's from the Mki and Mkii's, you only need to bias the 6550's. If you have a multimeter and the Audio Research bias tool(looks like a screwdriver with a small blade and wooden handle) its a straight forward process. Although i install my own tubes and bias my VT100 Mkiii, I still buy my tubes from ARC. They are more expensive but if a tube fails, Arc has a 90 day warranty period and would cover appropriate repairs. Its just a risk decision on how much you trust your local Tech or yourself.