90 pound pressure works fine, and the most important thing is that the open and closed length match the old ones as closely as possible. You can measure the approximate open and closed lengths on your old ones before removing them.
I found my original package when I replaced the struts. It says NAPA 819-5521. I may have used some of the parts from the old struts too. Possibly the ends I'm not sure. Good luck and let me know if it works out.
I will try to get that information for you, bear in mind that was a while ago that I bought those parts.
