105 GTV Gas line questions

[JALFAjr@domain.elided]

I am in the process of replacing the steel gas lines on my 1971 GTV.  The 
original lines were wrapped in some type of rubber covering, probably to 
reduce heat acquisition.  

My question is, how important is the covering?  It appears to be the major 
cause of the rusted fuel lines, but I have had temperature induced pump 
cavitation before, so I want to make sure that if it is necessary, I get some 
sort of replacement.

The next obvious question, does anyone have a good source for the rubber 
covering?

John Justus
1971 1750 GT Veloce (fuel lines ready to go and then it comes down off the 
jacks and ready to roll)
1995 164Q

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