The fuel tank tubing should be .70" diameter. That fits inside of a BT-20. Totally Tubular (Jim Fackert) has tubing that is that diameter. Here is a link to what he sells, and yes it is dated 2003 but still good.

http://www.wooshrocketry.org/misc/tt.htm

FWIW - My Saturn 1/70 Saturn IB drawing linked below. Has full size and 1/70 dimensions. You'll have to work out your own 1/100 dimensions. But then it is not hard to mentally move the decimal two places to the left.

http://homepage.mac.com/georgegassa...B-70-100pct.gif

I am also going to include it attached below, as seen in the thumbnail. But it is so large that it may become shrunk during the process. So use the above link to download it at "for sure" 1/70 scale.

- George Gassaway

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