Yes I did this for my 57' with EFI.
There are more pictures in my gallery
It can only be done with a
new sending unit.
I purchased a new fuel pickup/sending unit for my stock 57 tank.
I drilled a hole another in the sending unit and soldered in a line.
http://www.ebay.com/itm/1955-1959-Ch...item2828ab950a
http://www.ebay.com/itm/HARRIS-STAY-...item5438545eeb
http://www.ebay.com/itm/NOS-Jeep-CJ-...ZW4w27&vxp=mtr