cleaning fuel line

You might try ramming a semi-stiff wire through each end and see if that helps. (thin wire coat hanger?) I just saw that Eastwood sells an aerosol spray can with a funnel tip that they say can be used to clean out fuel and brake lines. I don't know how effective that would be. I doubt it would have more pressure that an air compressor and I don't know how effective the cleaner solution is.

I'm in a similar situation as I just dropped the tank in my 64 Valiant a couple days ago. It's been off the road since 1982. I was working on the rear brakes when all of a sudden the fuel tank decided to start leaking! Rust under the strap so there are pin holes. The inside of the tank looks almost new and is very clean. I used a scope to check the inside and although it looked good, I can definitely see holes. I have a new tank, sock, float, etc. on order but have not checked the main line yet, DOH! Gotta do that tonight. I may be in the same dilemma as you.