Dumb question - sending unit

[CoronetDarter]

So, got my gauge cluster back in, sending unit back in the tank. Took the Coronet out, got some gas, and promptly had a gas leak coming from the tank.
I'm second guessing myself now - does the rubber sending unit gasket go between the tank and sending unit, or between the sending unit and lock-down collar? I put it between the unit and the collar but I don't remember how it was when I removed them.

 

[Grady Cain]

Seal first, then sender, then lock ring.

 

[CoronetDarter]

Seal first, then sender, then lock ring.

Thanks Grady. That was my mistake, reinstalling the gasket on top of the unit.

 

[CoronetDarter]

Sending unit is in, gauge works and no leaks. Thanks again.

 

[67belvedere/225]

I found that the jobber rings need to be bent so they crush the rubber gasket properly