Good tip, Joe! Gives me something else to try next time out (besides smashing mole piles).
As for what glowplug to screw into your donk, Thunderbolts
rule! I normally carry 4 stroke and idle bar, tho there are other T-Bolts that will work. Dirt uses the "Regular", which seems out of character. The two seem to cover the bases just fine. I have been running the "free" OS A3's in my .25LA with no complaints. I did notice that they're kinda shorter than a long, and longer than a short. That might make them run a bit cooler than desired. I expect they'd otherwise be about as hot as a Thunderbolt 4 stroke, which is not fitted with the coil shroud like an OS "F".
Must say, I have a poor regard for Fox glowplugs, having seen too many instances where replacing one with a Thunderbolt made such a huge improvement. I believe Brodak carries "Merlin" glowplugs, and I'd suggest trying them, if that's easier for you, as a Brodak dealer in Oz. They have a very good reputation, but we don't get them out here on the West Coast, near as I can tell.

Steve