I retrofitted PAS to my 79, the front pulley needed sourcing and the pump needs to match the engine as Seb says. It does work but the belt alignment isn't great.
I got around the issue by fitting the b230 to match the PAS
I meant to swap my ball joints, or more specifically replace with the correct type when doing my front suspension, but my mechanic replaced like for like without asking as it was needed at mot time.
I've never experienced any issues with having the reduced castor, so don't feel any need to fit the offset type. They're inexpensive either way...