I was almost in an accident because of my LSPV and that convinced me to remove it. Once removed, I found that the LSPV was way out of adjustment and rotten with rust and old brake fluid. A union from Advanced Auto was cheap and easy to install and fixed my brakes.
I just did something similar.
Brake booster failed while we were on vacation. I limped the Cruiser home and ordered a new booster and MC rebuild kit.
Rebuilt MC
Installed new Seiken Booster
Adjusted booster rod with the Corvette tool
Replaced brake lines with SS lines from Manafre
Bled...