brand new member here with 77 2.7 CIS questions

[eschoeffler]

Hello all,
Brand new to the forums here, as I just got my fathers 911 out of a 40+ year slumber in the garage. I got someone to get the car put together for me, and now i’m on my journey to learn about it.
My problem is with CIS and specifically cold start. Once up to temperature, warm start is no problem.
Engine was rebuilt and drives great. New Fuel tank, pump, accumulator, lines and injectors. Fuel distributor and WUR has been cleaned. The WUR has an adjustable screw added. I bought a fuel pressure tester and found the following.
I checked for power and had it at the WUR and aux air slide.
From the porsche manual, at 20 degrees C I should have between 1.8 and 2.2 bar, but mine came in low at 1.5 bar.
System pressure is 4.85 bar
With WUR plugged in @ 3 minutes reads 3bar
After only 1 minute there is a 0 bar resting pressure

Looking at the top of the WUR I can't see any numbers on top as I've seen on others online.

With all this information my fuel pressure is a bit low, making a rich mixture and my resting pressure dropping to nothing points to a serious leak somewhere. Where do I start. I don’t have a vacuum tester, but could get one if that would help.
Thanks in advance,
Eric