Can I swap the sending units in my 79 f150 with dual tanks without dropping the tanks?

 

No sir. Unless you pull the bed.

 

Thanks, I thought that would be the answer, but I hoped not...! <grin>

 

X2 for sure NO on the rear tank, unless you have a 1" too 3 " body lift. Or like Jflem said pull the bed. Get under and look, you can not get to the lock ring to tap it loose. And I am sure the sending unit has to be rotated when put in and with the tank installed and the bed on no clearance at all.

And cutting a access panel in the bed is NOT a good idea either. Gas tank drop walk thru below.
https://www.ford-trucks.com/forums/1...l#post14696841