We had to remove the fuel tank sending unit because the gauge was not working and had to send out the fuel tank to the radiator shop to get cleaned out.

The sending unit arm was froze in place with rust so I ordered a new sending unit.

The point is that the slotted head machine screws were hard to remove and the heads were previously a bit stripped so my plan was to use hex head machine screws.

Then I thought I should use stainless steel machine screws.

So what are your thoughts, should I use:

New slotted head regular steel machine screws

Head hex regular steel machine screws

Stainless steel hex head machine screws