Electric Vacuum pumps

I was given a new Hydroboost unit for free on the condition that I install and test it and give a review on what I did to make it work.
I got almost no help from the supplier since the deal was that I was supposed to be doing the research and development of it.
I measured and fitted the lines and had them made. I sourced the fittings. I found a late 90s Chevy truck with hydroboost and got the power steering unit from it. It was a Saginaw unit line many of our cars came with but with a bigger reservoir and two return nipples which you need since both the steering box and hydroboost unit have pressure and return lines to them. I bought a new pump and swapped it into the Chevy reservoir and followed the bleeding instructions to purge the system of air. Steering was notchy at idle and the hydroboost provided no assist. I revived up the engine and it made no difference. I bled the system again. The fluid was full, the pump never squealed but I had no boost. I messed with it a couple of days until I had zero steering assist at any engine speed. The pump was dead. I warranteed the pump and swapped another one in with the exact same results.
I rarely blame others when I’m having trouble with a project, I look to my own possible mistakes yet I couldn’t find any. The lines were clear, they were routed properly. I tried a 3rd pump and again, slight steering assist at idle at first and eventual failure. Screw it… I pulled the POS and got rid of it. The vendor had me send it to some other guy and I never heard if he got it to work. If he did, I’d like to know how. I’m still unsure what I could have done wrong.
From what I’ve read, hydroboost works great but can be really sensitive, especially in a light car.
Good luck