73 duster - gas gauge not working

Im ordering the sending unit now but I wanted to know what you guys thought about getting the larger size fuel line choice.

Mine is the smaller line but I plan on going with larger motor (360) in the future.

Would I run into problems if I got the larger size and then necked it back down until I got the cash up to just redo all the lines bigger?

Or will a 360 run fine on the small lines?

Get the larger one now, and you won't have to wonder why the car won't accelerate right when it has the 360 in it. :D
Necking down won't be a problem.