When I was racing in the mid 70's I used a cut up and hole punched tunafish can [thick] a beer can [thin] and spark plug washers to shim the shaft. It was a couple hundredths quicker with less preload.
If you want your fuel line in the factory position, put it on before you install the frame connectors. The US Cartool connectors have a provision for the fuel line to pass through.
Growing up my dad would take me to see my uncle run a Funny Car in the 60s. Then early 70s Pro Stock . He later ran modified with a Sox and Martin built Hemi Challenger. When I turned 15 I thought I knew about racing so I took my Honda to the track. I won the first race I ever entered.