Instead of trying to remove ignitor while mounted to burner, I removed burner/ignitor assembly by detaching it from the oven frame and pulling the ignitor/burner assembly out so connector cleared the access hole. Disconnected and removed whole assembly. Then had easy access to the mounting screws. Removed screws by first spraying threads with WD 40 and waiting. Screws were oxidized so they were damaged when backing them out, as were the threaded mounting holes in the burner ignitor bracket. The screws are not sheet metal as noted in other posts, but rather are 10-32 machine screws. I chased the ignitor mounting bracket threads, then remounted the ignitor with 10-32, 3/8's, cap head, stainless bolts with a stainless star washer (available at any ACE hardware or other similar store) -- that way you don't have to tighten up so tight (just snug them up) -- unless you expect an earthquake every other week. The stainless screws helps retard the corrosion brought on by high heat and any moisture that settles on the bolt threads as the system cools and with subsequent starts.
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