Yes.
Yes.
A few items...
1) There is a '15 psi' regulator built-in (red circle)...
Supply on the left, return on the right.
2) The only potential issue that I see is the size of the return side. It needs to be large enough to flow all unused fuel at low demand (such as idle). The internal orifice's are pretty small, so it may take a little massaging to make that happen.
3) The regulator is nominal at 15psi, but this specific regulator is 'all over the place'. It will probably require some attention simply becuase I think your potential HP out ways the flow capacity of your injectors.
4) Which brings us to... which injectors do you have? The most common ones I see are #5235206. See red circle...
Those are rated for 55lbs/hr at 13 PSI
The 9C1 police cars came with 65lb/hr at 13PSI
There are several others if you dig.
5) I understand all these Rochester injectors are perfectly happy at 30-32 PSI. And some of them are good to around 70 PSI.
I see no reason you couldn't take the stock Datsun regulator and piggyback it on to the GM regulator (essentially overriding it). 36-38 PSI *might* work just fine with those injectors, and you're probably going to need it.