Well, if memory serves me correctly, once we drilled the hole, and used a die to thread/tap the drilled out hole, we then placed the sending unit (into that hole) and then torqued it back into (the original opening) as one solid piece.
Never thought much about having to remove it, or take it back out quite honestly.
I chose to think of it as a permanent install, rather than something that'd be R&R'd with any degree of frequency.
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