I assume TBI uses the same 40-50PSI as MPFI? If so, that pressure may make it difficult to connect the fuel line to the regulator. I don't know that a rubber hose and a clamp will hold that kind of pressure

If it will, or if you can fab a more secure line to the regulator, AND a regulator can step 40-50 PSI down to 6...then I'd just run a dead head set-up. No need for a complicated return system on a stock daily driver build.