Fuel leaks floods interior of my Targa

[aldolente]

Good day all,
I justt received my freshly restored 1980 targa. The 3.0 liter engine was total re-built. The car had all new body panels, lead work and was freshly painted. I received the car Saturday after three years in the shops. It was my intention to do the interior.
I installed some Dynamat and other sound proofing Saturday. That next morning I found fuel all over my floor pan and in the shiftier tunnel. The fuel filled the tunnel up to the knuckle of the linkage. I disconnected the battery and pulled the relay as there were open wires in the area. Thank the heavens something didn't spark and destroyed my car, house or worse.
I suspect that the main high pressure or, less likely, the return fuel lines burst. The system sat for three years with no fuel in the lines. all other fuel lines were replaced. It could be something else but i have not seen any fuel on my garage floor and the bottom of the car is dry. The luggage are is dry too. No spills or wet in the engine areas too.
Is this something that happens after time? Are the fuel lines to be replaced after so many years of use? A leak in this line can destroy a very expensive interior. or, is this justt a rare case? I just lost some expensive Dynamat that melted from the fuel. I am used to being told by my mechanics that "they never saw that before"!
Also, how hard is it to replace the lines?
Thanks guys.
I will upload some pics of the beast once it is done. it looks great. It is Bilk/bilk/bilk!

[aldolente]

Anyone ever replaced these lines? What special precautions or difficulty will I face if I do it myself.
Anyone ever replace them with after market steel lines?

[sww914]

You might try posting this in the 911 forum, It's more likely that you'll find somebody who has experienced this in that forum due to the greater traffic there.
I replaced the plastic lines through the tunnel in my 914 with metal, it wasn't too hard, but I doubt that much of it applies to a 911.

[Laneco]

The fuel lines are replacable. Not at all fun, but do-able. We got to do them in Steve's 80 after a welding incident on the floor pan damaged one of them...

Use the line you remove to pull a fishline through the tunnel. Then use the fish-line to pull the new line back thru. This works better with two people. The lines go thru securement points in the tunnel, take your time you want the new one in the same exact place!

If the other person is your wife, please don't scream at her if she accidently forgets to secure the fish line to the the new fuel line and pulls the fish line back thru the tunnel... If she is like me, it will hurt her feelings and your dinner will be deliberately burned.

angela