Issue with installing Stewart Warner temp gauge sender

[Giraffe]

thats an awful strange looking reducer bushing. With no hex on it, I sure hope you never need to remove it. Then again I'd really wonder how it got tight enough to seal with no way to turn it in there.

Intake is 3/8 NPT, going to guess the sender is 1/8 NPT. Looks like too much flat space for it to be 1/4.

This is the kit I bought. However, it didn’t come with the adapters pictured. It’s just a simple 3/8 to 1/8 NPT adapter. If I ever have to remove it, I won’t try to save it. Trust me. It’s tight.