this comes up a lot and i have yet to see a decent diagram as to what ports on the throttle body see vacuum (ie after throttle plates)

the ports labeled vacuum are after throttle plates, so they read vacuum and boost. These sources work for FPR, boost gauges, pressure sensors, BOV

the ports labeled boost only lead to before throttle plates, so they read only boost or are just a fresh air source for n/a. These sources work for OMP line source, injector bleeds, and boost controller solenoids, etc

is this diagram correct?

 

I don't think that is correct. I'm going from memory here, but I'm fairly sure that all the ports on the front of the throttle body are vacuum, while all on the rear are air ports. This could be wrong so you might want to wait for someone to confirm. For years whenever I have done standalone installs I have just capped all stock ports and installed a vacuum manifold on the firewall.

 

I checked that middle port and it doesnt seem to see any vacuum, it leads to a tiny hole right in front of the main throttle plate (s4 TII)

 

So, you're only talking about a US-spec S4 TII TB, right? Because J-spec and NAs and S5s are all completely different.