I purchased a used IR-12 Dietrich roaster. It is number 8 and was made in CA before Stephan Dietrich moved to Idaho. It was very dirty and neglected and we have been restoring it. Since Stephan has left the company and retired, hardly anyone there knows much about these older machines. Does anyone have one of these older machines made in the early 1990's. My main concern is the gas regulator that controls the heat for the roaster. The original part is no longer made and I am trying to figure out what to replace it with. The original part had a handle that went through the front of the control panel to adjust the gas flow. Any help would be appreciated.