Moses, thanks for your detailed and quick response. I forgot to mention that this engine was rebuilt a year ago. O2 sensor is brand new NTK. All other sensors have been tested either with OBD tool or with scope and seem to operate properly. In some cases I had spare ones that return same values.
Based on part number I installed proper fuel pump. I tested for bleed down and it held pressure for more than 30 mins. I will preform the test at fuel filter. Can I simply remove fuel filter and put tee instead of it?
What bothers me is that with both old and new regulator there is fuel odor in vacuum line to the regulator. It is not extremely strong but definitely present, so I'm not sure if that is a sign of leak... With old regulator (factory installed one) long ft numbers were around 3-4%, while with new one that went higher. I'm not 100% sure but I think that with old regulator fuel pressure was close to 30psi. I replaced it because I could smell fuel odor in vacuum line and because I replaced fuel pump before that but pressure stayed below 31psi. I could not see any fuel dripping out of it.
Another thing worth mentioning - when I first installed new regulator, on idle it was sitting at 37psi with vacuum line either connected or disconnected. I checked line multiple times but it was ok. Then after some driving it went down to current pressure. Could this be that this regulator is bad from the factory? Maybe it was not calibrated properly.
I will again do smoke test. Last time I did it only place I could see smoke coming out is throttle body shaft but I guess that this leak can be compensated by IAC motor. If I hook up jeep to OBD tool, I can see that IAC steps are 7 on hot idle, not sure if this is normal.