New Gas Tank New Lines???

I have a new blazer surplus diesel tank I plan on mounting in the rear between the rails on my 51 Chevy 3/4 ton. I want to keep the tank behind the seat and use both. My question/s are: I would prefer to use hard line but don't know what kind or size. I don't know if I should use fittings like my brake lines or rubber hose with a clamp. I don't know what I need to use to set-up the integration of the two fuel lines. Will I need a solenoid valve for shut-off or just run the two together. What is best? :confused:
Any suggestions will be appreciated.
SBC with 700R4 tranny
Pics at: http://community.webshots.com/album/556111970egYVwn

You can use brake line and there is 3/8"dia available. You could also use hard line and flare it with JIC 37 degree stuff and then use AN fittings. Dont use rubber hose for long runs, use it a flex points only. Keep the rubber part short if you can.

You have to have a switch in the line UNLESS the bottom second tank is above the bottom of the first tank and the top of the second tank is below the fill tube cap on the first tank....makes no sense, does it? Usually, you would plumb in a valve to switch the tanks, the fuel gauge wire, and the return line (if you have one). For a return line valve, an 85 or so Chevy truck has an electrical (solenoid operated) valve that includes the return line and the gauge wiring. This way, you can have a switch on your dash to change tanks.

There are also manual (lever type) switchovers that mount on the floor and go thru to underneath the truck. There are lots of sources for the manual valve. Look at LMC Truck for the stock Chevy switchovers.

mike in tucson

Some fords in the 80's have switch operated dual tanks. my grandfathers '88 150 does, his '95 does too but that's likely computer controlled