Part 2 of 2:

Since I'm installing a piece of avionics (a Grand Rapids EIS) very close to where the left fuel line comes into the fuselage, I wanted to clarify the clearance issues there. I inserted a short piece of fuel line through the fuselage and slid the EIS into place. It'll be close, but as long as the fuel line bends forward immediately after passing through the fuselage skin, I think it will be fine.

I drilled out the fuel line holes on both sides to just under 7/8", and installed a rubber grommet in each. I'm glad I won't have to modify the fuel line entry point.