The flow as pictured is from bottom to top. I am on a slab.
I saw Lowe's had same one as I have but didn't see how to just replace with same and not cut anything. Ya, the one side has the union but the other is a PEX crimp.
I ended up getting a larger and much more expensive one - thinking maybe will not have this problem again with a better quality part. Also figured the extra length would be perfect and give me some excess existing PEX line to work with.
But long story, comedy of errors, and using poor tools....I got it done, but not without much fuss. Basically, I added sharkbite fittings to each end of new pressure valve. But that run of line is pretty short and Ts off thru studs just a little above the valve. So that made the short run of 3/4" PEX have very little give so it was nearly impossible to get the last sharkbite connection. The line needed to push apart and then come back together and it simply wouldn't since the T above was stuck and just below is where the main city water line pops up from the garage floor so it won't move either.
But it's done, not leaking, and gauge now reads 56 psi at the hose bib. Pipes are quiet.
Only thing left to do at some point is fix a splice I made. While trimming the tube with the $16 Lowe's ratcheting tubing cutter, I kept getting angled cuts. Next time I'll just use a mini hacksaw and clean up the edges. But that left me with lots of little angled cutoffs and the existing pipe about 3/4" too short. I had a brass barb connector for 3/4" PEX but it doesn't take up much space. So I used it as a template and made the same thing on the lathe out of 7075 aluminum but with 3/4" space in between the barb ends. I used the stainless PEX clamps to secure it since I have that tool, but not a regular PEX ring crimper. Working great, but aluminum isn't used in residential plumbing for a reason I assume so probably shouldn't leave that piece there long term.
Made this and to same diameters everywhere, but the part in the middle is much wider acting as a spacer.