Monster S2R fuel pressure regulator

Hello--
I am working on a 2006 Monster 800cc S2R. I bought this bike last December off Craigslist. It had been wrecked, someone bought it from the insurance company, then sat for 3-4 years; guy never got around to doing anything with it, so sold it to me.

Okay. Fuel tank was half full of water, fuel system was rusted up, so on.

Drained tank, let it sit for a month, swelling went down. Had trouble getting spark, got that worked out. Replaced pump and filter. Fueled up, no start. Contacted eBay fuel pump seller "never had that problem, but we'll send a new pump"...great customer service. With new, new pump (and another new filter) still no start.

With ether, popped and ran briefly....

Okay, long story (sorta) short...fuel pressure is only 10-15 psi. We need closer to 44-45 psi. Borrowed a tank/pump assembly, it puts out 45 psi and voila...engine runs.

So, neither of my two new pumps is not putting out. Or maybe...the fuel pressure regulator? Ducati parts diagram does not list this part separately, or as being available.

I did some extensive googling, and while a number of 748/996 issues pop up, the S2R unit is totally different (mounted inside the tank, on the flange.)

I'm thinking I'll take it apart and see what's inside.

If you have any ideas or experience, I'd appreciate it.

Thank you, Rich