Should be easy, since you already have the modern fuel line with a clamp. You might need to make up a size adapter, as ISTR the early fittings took 5/16 id line, while the later ones are 1/4"; but that should be easy enough. One way would be to put a "universal" fuel filter in the line, using 5/16" on one side and 1/4" on the other.
For the line between the carbs, I used copper refrigeration tubing to make up a hard line similar to the one on later TR3 and early TR4; but you could make it all soft line.
In case it's not clear, the upper right fitting (in your photo) is the fuel inlet from the pump. The lower right fitting (which is somewhat bent) is the outlet to feed the rear carb. The short fitting to the left of it is the bowl vent.
On the rear carb, the fitting on the right is the fuel inlet (from the front carb), the other fitting is the bowl vent.
The bowl vents originally had short sections of soft line, plus a short length of hard line bent into a 90 degree curve. On the TR, the curved section was turned so the bare end stuck into the air cleaner for that carb.
What I've done instead is to omit the hard line, and use much longer lengths of soft line which hang down to the frame rail. That way, if the float valve does stick open (or get blocked with a piece of crud), the fuel gets dumped on the ground instead of into the air filters and down over the hot exhaust manifold.
This doesn't show much, but maybe it gives some idea