You have not stated your fuel system plans, but I have a feeling you may have far over-sized your setup in your mind. Let's assume you have a Pi running about 150hp. It will need about (150*0.5)=75 pounds per-hour of gasoline/petrol at max power. 75 PPH is 75/6 = 12.5 GPH or 12.5*3.7854 = 47 LPH. Yes, 47 LPH.
I like to add a random 20% flow for things like dirty fuel filters, cheap fittings and other restrictions, so 47*1.2 = 56 LPH
Considering a typical 30mm motorcycle pump can do 65 LPH or more at 3 bar, something like a Bosch 044 or Walbro 255 is lots of wasted flow, space and money. Using math, we find your 150hp consumes about 6.7 ounces of fuel at max power in 15 seconds. Typically for street or road racer, the accumulator (surge tank or swirl pot) is sized to feed the engine for 15 seconds at full power without main tank supply. Yes, that means your swirl pot with the pump inside
will be about the size of your fist.
I think you can see where I'm going with this, and that all of those parts should easily fit in your engine compartment or virtually anywhere along the line. And, they are all rated for exposure to the elements. Keeping in-mind that large pumps use more power, and can override the regulator with excess flow, knowing that everything over 47 LPH is excess flow.
Considering fuel lines the size of a drinking straw can feed 500hp at EFI pressures, likely your stock line is more than adequate. Use care to avoid planning a mismatched fuel system for a monster when isn't needed nor even wanted.
Dead-head fuel rail? Yes it can be done, but you are right, they do carry some drawbacks. In OEM cars there are purge valve controls, temperature sensors, and other stuff to make them work reliably with their quirks. Go for it if that's your thing, but generally with simple EFI a simple return system removes some of the unforeseen headaches. Using reasonably-sized lines should also be relatively inexpensive and easy to handle as-well. Hey, you asked, so there is my 'IMO'.
Just for ideas; the popular Honda TRX/VT fuel module (accumulator/swirl pot) with internal 65 LPH pump, smaller than a beer can. Designed for bikes and off-road things, it can be mounted anywhere and survive: