What size for fuel lines?

[In The Ten Ring]

OK....so maybe I didn't know what size my fuel lines were!

Here is my quandary......I am about to replace all of my fuel and vent lines but I am unsure as to what size to use.

Using the link below.....what size should my fuel lines be for a

1972
250 inline 6 cylinder
2 wheel drive
1/2 ton
manual shift

I'll need sizes for all fuel lines and vent lines.

THANKS!

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=135