RE: Glow plugs... need some suggestions
Troy,
When I raced boats it was common for guys to buy 100 plugs before the season started and end up with a handful by the end of the year.
Use the scientific method, don't change more than one thing at a time. I'd start by fattening it up about 1k from peak as Bob noted. Then switch to the K&B HP or McCoy plug. If those plugs are still blowing or turning dark brown like the one on the right then add .003" shims one at a time until the motor settles down. BTW: I always liked the McCoys better for testing because you can see the color change easier on silver plugs than black ones. They both run about the same in testing.
Now go off and tweak away then report your findings.
Good luck,
Chris