Great info Olly.Thought I should add something.
For those who might want an intank setup and don't want to pay the price for a rockvalley or rickshotrod shop tank, then this might help.
I bought a new tank for my 71 camaro and cut out the top and had a buddy weld a plate for the pump and sender.
I then assembled the pump module from Tanks Inc and the sender that would work with my original fuel gauge. The pump module works best with tank depths of 6.5' or deeper. I had 5.5' left after welding on the plate so I had to mod the fuel pump module to fit.
The pump then sits in a baffle
I made sure the welds were sealed and that they would remain that way. I used a fuel safe sealer on the inside of the welds and on the outside to. I then painted the top of the tank. I did not paint the bottom because I prefer the original look than the painted look.
For the fuel plumbing, I am going with a 3/8 aluminium supply line and 3/8 braided hose between the components. I have heard that braided lines can alloy fuel vapors to sip through causing the strong smell of fuel in the car. Aluminium is also cheaper.
For fittings, I chose to go with stainless steel compression fittings and endura finish hose ends. Here is a pic of the fittings on the Corvette FFR.
The parts#
3/8 compression fitting. Goes onto the 3/8 supply in and out SS-600-6-6AN
5/16 Pipe reducer. goes from 5/16 return to a 3/8 pipe allowing use of the above fitting SS-500-R-6
These fitting are from swagelok