Elite SB50 Gas tank de-rusting

[wrkey]

Picked up a little 1988 Elite that was running but surface rust in the tank. The petcock was plugged up and the in tank filter was small pieces. I have an '82 Aspencade that had the same problem and I cleaned it (6 years ago) with vinegar and it did a great job. I want to redo that process to clean this tank... however, I have a concern.

The fuel level gauge screws are frozen solid and I'm afraid to exert too much force as they may break off. So... taking the fuel gauge off isn't going to happen. With that I am concerned that if I use vinegar it will have a bad effect on the plastic components of gauge and the float.

Are my concerns legit? If so, what's a good alternative?

Thanks in advance for the help and I am sure I will visiting the page often as we get the little gal running.

(Yes it is pink and yes it is for my lady to ride.)

[Wheelman-111]

Greetings:

I can't see vinegar harming plastic. Tap-tapping with a hand-held impact screwdriver might get the gauge off?

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