Diesel Bombers - Issue with wiring ISSPRO Ev2 FP gauge...

Was wondering if anyone else has gone through this... Basically, it seems the directions might be a tad vague on certain details...BUT, here's where I'm at...

Installed Ev2 FP gauge(electric), with tapped banjo bolt. I installed the banjo bolt in the line between the filter housing and the vp, at the filter. Followed the directions for what I thought to be to the letter...I currently have no gauge reading, and no illumination. Grounded gauge inside, to a bottom brace on the dash, and was proven good. Tapped blue wire from ignition, found to be a good switched 12v source, and installed 3A inline fuse per instruction. Ran the other 3 wires from the sending unit to the gauge, and installed them per instruction.

Now, the confusing part, there is a wire listed as +5v, but it is getting 12v, I'm guessing being backfed through the gauge. There is also 12v coming back from the sensor to the gauge, but I have no needle movement, anyway. Now...is that 5v wire supposed to be tapped into a 5v from the truck? Because the instructions are telling me to run it to the back of the gauge. Also, the ground to the sending unit itself...should it be spliced, and grounded to the truck also?

I also probed the dimmer switch to find a tan wire, that changes with the dimmer switch, and varies the voltage between 5-12, but no illumination in the gauge. Any thoughts?

Here is a pic of my power tap and ground. I found it done like this in a how-to somewhere, though I forget the website. My power and dimmer were both soldered and wrapped.