Thanks for all the input, Guys! I replaced the glow plug harness a few years ago with a brand new OEM GP harness that I got from Uhaul, so that "should" still be in good shape. I got one of the last OEM GP harnesses that Uhaul had. While No. 7 has gone out 3 times, No. 5, No. 4 and No. 2 have also burnt out, so it seems more or less random. No. 7. along with 8, are the hottest cylinders, so that may be why No. 7 is more susceptible to burning out. Plus, No. 7 is under the turbo and difficult to change out, so for that reason alone, it will be more susceptible to burning out just due to the general contrariness of things. Timing is good at 8.6 degrees timed with a Kent Moore meter. I am thinking the controller is the culprit, and I will see how the replacement controller does and report back after a while. Again, thanks for the input!