I am pretty sure from memory Joe that the red and green wires are common points. Just make sure you have current available at those wires. If you don't have the headlight test lamp bare some light gauge wire and separate the stands so you only have a couple to melt and short out between the red and green briefly. It should spark and melt the fine wire, don't do it too long or you may blow your main fuse. You can separate one red wire then one green wire and test on the rectifier end if they are a common point as I think.