77 k5 4 port sending unit instead of 3

[77ck5]

Can i use a 4 port instead of a 3 port sending unit and just plug the 4th off? Gonna drop tank tomorrow finally and it looks to be a 3 port but hard to tell with it installed. I know 1st port from left is filler neck and 3rd from left is feed to motor. Would return line go to the 2nd port with what i believe is a check valve and plug the smallest port ?

 

[imiceman44]

Can i use a 4 port instead of a 3 port sending unit and just plug the 4th off? Gonna drop tank tomorrow finally and it looks to be a 3 port but hard to tell with it installed. I know 1st port from left is filler neck and 3rd from left is feed to motor. Would return line go to the 2nd port with what i believe is a check valve and plug the smallest port ?

View attachment 534769

I am pretty sure you can.
I can't see well to confirm which is which.

 

[77ck5]

Is this better?

 

[Blue85]

When you pull the old one, you should be able to compare the setup. The problem will be if one (or more) of the line sizes is different. When you cap one off, be sure to use a material that is safe with gas. That's a tough location to replace later.