It sounds like you have the older all gas valve control system. I have not had one of those older ones off. I have had the newer ones with electronic ignition.
Looks like this, just I'm doing a tank flush in this pic
I'm assuming your question may stem from how to get the sensing unit out to unscrew out of the tank?
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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