You may be in for a bit of work.
Not sure what year GM changed the fittings, but when I replaced the power steering/hydro-boost pump on my 1980 454 P-30 Itasca a few years back the old pump outlet had a double-flare fitting, the new pump had an O-ring fitting. I was able to remove the double-flare fitting and use it on the new pump which enabled me to re-use the old high-pressure hose.
Later, when the Hydro-boost unit failed I could only get a Hydro-boost replacement unit with the O-ring fittings. What a PITA. No one had a newer O-ring style hose for a P-30 that old, and anyway I now needed a hose with flare on one end, O-ring on the other. I got some steel brake line, replicated the shape of the pump end of the hose with the double-flare using a tubing bender and a flaring tool, and spent an hour in my local auto-parts store with a very helpful staff member who let me go through their power steering hose inventory until I found a hose with an O-ring end that would fit my new Hydro-boost unit. I bought the new hose, cut off the steel end, threw the hose away and re-bent the steel section to match the profile of the old section. Then went off to a local hydraulic hose supplier and got them to make me up a hose using my steel ends.
In the end it all worked out great but what should have been simple turned into a major project. Keeping the old units on the road is always a challenge but can be very satisfying for the do-it-yourself-er.
PM me if you'd like, I'm sure I have pictures of everything if you're interested.
1994 Bounder 32, F53, 460
