I have not done it yet but I do plan to use a hydrobooster and no power steering pump. It has been done before.
One piece of advice I've seen on the matter is to use a high pressure hose and appropriate fittings for the return to reservoir, this is the line that would have gone to the PS gearbox. You also have a 3/8 hose return from the hydrobooster, it goes to a nipple on the reservoir just as usual.

I will use a GM type II pump also called a Saganaw TC pump. They make a lot of versions of that pump and some lower flow and lower pressure, and or a fitting or valve can be swapped to reduce pressure. I'm thinking low flow and pressure is what I'd needed but still need to do some research and or ask some of the aftermarket/performance hydrobooster dealers.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-