MG Car Repair: Run on valve wiring, marvel mystery oil, hot point

Question
I have a 1977 MGB and am replacing the run on valve(ROV). The problem is that the original ignition on the column was replaced with one on the dash. The old ROV was broken and they did not hook it into the new igntion. The new ignition only has four points for wires to connect where the original had five. I would like to run a wire from the ROV directly to the ignition but am not sure where to attach it. As long as it is a hot point would it matter? This car diesels bad when it has warmed up and will not shut down. It is timed correctly and idle is set to 800 RPM. I have ran water and Marvel Mystery oil through the carb to clean out head and cylinder deposits. Still diesels. The run on valve is my next step and I am not great on wiring, which by the way is a mess on this car.That's a whole different story. Maybe later.

Answer
Hi sorry about my delay in reply. I am not very knowlegable about the ROV circuit. I would first suggest that you obtain a full car electrical schematic diagram. It will certainly help answer your question about how the ROV is wired and to what points. If you decide to direct wire it to a hot circuit, make sure it is fused, and I would only put it to a circuit that is wired through the ignition switch so when the ignition is on, your circuit to the ROV is open (or closed) and when the ignition is switched off - the ROV circuit is closed (or opened) as the case may be.

Hope this helps. I do not have the 77B wiring diagram or I would attach.

Brian