This looks to me as if your 911 has a circulating fuel system (two hose green circle).
On the other end (carbs), it seems to be ‘dead-end’.
You are a prime candidate to re-do the fuel system
right.
A number of years ago I posted a well-thought description of a fuel system on Early_S_Regestry.
Unfortunately, one of their reconfigurations lost that thread and post.
I’ll try and reconstruct my design here.
The critical issue with a fuel system for your 911 is safety.
Too often not all the issues are taken into consideration.
Perish the thought that we should ever crash out 911s while racing.
It can happen and we need to be prepared with our
design.
I’ll try and help with my lame experience.
Not today. I’m glowing in the dark after some nuclear medical procedure. Keep after me.
The basics are to have everything easily serviceable as you go racing and have the fuel system tolerant of crash damage.
Your life may depend on your (our) good engineering.
Same with your fire suppression system.
Best,
Grady