I am doing the same thing.
From tank to under cab I ran 3/8 inch Polyarmor tubing. I used 3/8 inch rubber hose into a Jeggs brass transition into 5/16 inch rubber hose. Then I ran 5/16 tubing until about 2 inches from the pump and another bit of rubber hose.
I had bought a pre-bent stainless steel hardline from Inline Tube but it leaked badly.
So I am going to do the same as you, stainless steel hose from Earl's (I think that is the maker) and -6 AN fittings. For the fitting that goes into the carburetor (Rochester Monojet) I had to order that from
www.quadrajetparts.com, a 7/8th inch piece. It only comes in red. It seems to fit fine.
https://quadrajetparts.com/adapter-i...ing-p-368.html
This guy would probably have the part you need for your pump also. Give him a call.
(908) 496-4188 **
Email:
Sales@QuadrajetParts.com
I bought some AN fitting wrenches and a hose cutter from Summit Racing. I also bought the vise jaws to hold the fittings while I put those onto the hose.