So, here's the final product installed. It's hard to say if it's going to last; the only way to find out is to just drive it. But at the very least, the brake booster now holds vacuum after turning the car off like it should. Also, it doesn't make that funny lil "squeaky balloon" sound when I step on the brakes anymore. So, those are all good signs.
Also, they kept the rod length adjustments the same as original, so I didn't need to readjust those when I re-installed the unit.
I dunno. It's good I guess lolol. If anyone else wants to get this done, check out Power Brake Exchange in Santa Fe Springs CA. They have a website too, which says they're located in San Jose. I guess they have a few locations. If you go to the one in Santa Fe Springs, talk to Luis. I think he's the main guy there.