Replacing a 1970 Charger Fuel Sending Unit Question

[Faiginwells98]

Hello, I am new to working on my charger, so please forgive me if I ask this in the wrong section or wrong way.

I have a 1970 Charger 383 4BBl.  Mostly in factory original condition.  The gas tank appears to be leaking, so I have opted to simply replace it with a Spectra CR9A tank.  I figured since I was replacing the tank, that I would also replace the Fuel Sending Unit, however Spectra lists three model numbers FG68A(B)(C).  The difference being A has a 5/16 in. Outlet, B has a 3/8 in. Outlet w/ Fuel Return, and C has a 1/2 in. Outlet w/ 1/4 in. Fuel Return.  I haven't removed the tank yet, as I was hoping to order the parts and have them all here before I started the process of taking out the tank. 

My question is, is there a way to tell what size outlet I need without actually seeing it?  In other words did the 383 always come with a 5/16 outlet?

Thank you for any assistance you can provide.

FW98

[cdr]

If your sender is in good condition, I would reuse it, the aftermarket ones do not read correct.

[Faiginwells98]

Thanks for the reply.  My gas gauge hasn't worked since I got the charger.  I just assumed it was easier to replace the sending unit rather than trouble shoot it.  Is there a brand of sending unit that works better than another?

[cdr]

they are all about the same, reuse the lock ring off the original

[BLK 68 R/T]

383 would use the 5/16 hose size with no return.

[cdr]

383 would use the 5/16 hose size with no return.

you sure about that on a 70 model. I am not,

I would look at my old one .

[BLK 68 R/T]

  I'm sure. 440 and Hemi would have the 3/8 with 1/4 return. 1/2 was never a factory option.

[Faiginwells98]

Thank you! 

Everything I could find seemed to indicate what you are saying.  I am going to order one at 5/16 and have it in case I need it.  That said, I think I have other gauges out, so I am going to get all of them checked before I replace the original sending unit, given CDR's comment that "the aftermarket ones do not read correct."

Thanks again for the help. 

[cdr]

I'm sure. 440 and Hemi would have the 3/8 with 1/4 return. 1/2 was never a factory option.

Who says the one in his car is original ?