The eng side of the bulkhead, the wire going to the brown wire on the ballast plug in. I have a stock well used 4 terminal ballast and it has 6 ohms on one side (which is way too high) and 1.4 ohms on the other and with both sides wired parallel I get 1.1 ohms which is perfect as the stock 2 terminal ballast supplied w the orange box kit is 1.25 ohms. See if the ballast has continuity and if it's getting fire