Well Kerry,

I am almost embarrassed to say that they worked all along and I didn't realize it. I was mis-informed and was attempting to use the wrong switch to light off the glow plugs. I had a feeling that this diesel was starting up way too easily for 50 degree temperatures. The glow plugs were working, just not getting enough warm up time. If you look at my previous post in this thread, you will see the aha moment when I finally figure out what that other switch is actually for. Duh! I did not know that the glow plug portion was actually built into the gorilla switch even after spending days looking at the wiring diagrams. Well, yes I did, but it hadn't sunk all the way into this thick skull yet.

It was due to the information from all of you folks here and looking at a few youtube videos on cold starts along with a good nights sleep that got me the answers that my tired out brain needed.

My brain seems to keep working on things while I sleep and the answers come to me in the next day or so, normally. It was just too overloaded to get the answers the first day or two. Seventy to eighty hour work weeks for this old fart are getting to be too much these days.

I had my son operate the gorilla switch slowly tonight while I had a voltmeter on #4 glow plug. I think my face lit up brighter than the meter and the salt shaker did when it kicked on.

The only thing I can say is I'm glad I didn't get frustrated enough to take a hammer to it like a previous post mentioned. These MB parts are way too expensive for me to be doing things like that!