If it's not really about tuning or wiring. Then it belongs in here.
Currently replumbing my fuel system after an intake manifold swap.
Front engine, rear mounted fuel tank. Swapping from a plenum type manifold to an ITB setup, N/A with a return type fuel system.
Any downsides to mounting the FPR back at the tank?
Being an ITB, I won't be referencing manifold pressure.
so long as you can keep the pressure you want to target at the injectors - you could mount the regulator anywhere you want - but the longer the run is that you have to keep pressurised - the easier it will be for it to have unwanted drops in pressure that could affect your tune.
my car runs a "dead head" fuel system - the regulator is in the tank and it runs a single pressurised line up to the fuel rail which is a dead end with no return.
It works well enough for many oems to use it, so if you size your fuel pump and lines (or oversize it) so you wont lose pressure at higher rpm and injector pulsewidths you should be able to keep it tidy looking like it sounds like you want to do. It would be easy to convert to that system as well if you have a current return style setup - its a pain to go the other way to a return setup from a dead head setup.
I'm all good with the 'hydraulics' of the setup.
Do you suffer from heat soak in your fuel rail on a hot restart?
Are you monitoring/compensating for fuel temp?
I've just done a rebuild including full floorpan replacement so all new brake and fuel lines to be fabbed. I have a 'clean canvas' to work with.
My fuelling is pretty much a factory setup apart from the injectors (1000cc's) and I have 0 problems on cold or hot or stinking hot starts with the alloy fuel rail and it does get rather warm at times. Even if the pressure drops due to sitting for a while - it still starts easily at any temps.
I don't monitor fuel pressure yet, that's coming after I get the oil sensors all plumbed in and monitored.
I'm also lucky as there is a composite fuel rail available for my engine as a bolt on replacement that I'll be getting at some stage. It claims to drop the temps the fuel sees in the rail up to 100deg F compared to an aluminum rail, and it can be plumbed either in the factory deadhead style or it has multiple ports for AN/sensor fittings so I could convert to a centre feed with dual return system and run fuel temp and pressure sensors as well - its on the ever growing, never ending list of things I will be buying, but it'll be more sensors before that gets purchased.
Your build sounds like its going to turn out very nice if your replacing whole floor pans for it :) Going to start a build thread on the forum about it?
With the greater fuel volume in the lines, especially if part of it is fuel hose, the less fluctuations that may be observed, so having it mounted at the tank rather than the rail may be adventageous. Heck, that's why accumulators/dampeners are fitted by many manufacturers, to reduce fluctuation spikes in the fuel pressure.
I assume you're primarily doing this for packaing and reducing engine compartment clutter, so if you're running all the paraphenalia at the tank, maybe on a mounting plate, it'd be a good time to incorporate a dampener.