Now I am not 100% sure of the USA Spec engine fuel system but think if you look in the engine bay where the metal fuel pipe comes from the fuel tank, this maybe on the passenger side of engine bay.
Disconnect the rubber pipe which joins this metal pipe to the fuel pump near the oil filter.
Might want to clamp to line from the fuel tank to stop leakage.
Run a new length of fuel rubber pipe onto the fuel pump & have enough length to put into a can of petrol which can sit on engine mount near the fuel pump.
Hopefully one of your US Guys can confirm - Washington DC also rings a bell & think someone on this site lives there.
Oh yes you can download a TR7 Works Manual from this site which helps
http://www.triumph-cars.co.uk/tr7-pdfs-various.html