Ive not seen a 1/2 unit. I recently stepped up to a 3/8 fd 1/4 return from a single 5/16th feed unit. cut the 5/16th off the old and welded it onto the new in place of the 1/4 return giving me a 3/8 feed with a 5/15th return. But that didnt work out so well. The sending unit is so thin It warped the top enough to where it wouldnt seal. It also got the rubber seal for the fuel level sensor wire to hot and it caused a leak there as well. I got so mad and frustrated trying to seal it up I just went out and bought a sumped fuel cell with 1/2 exits.