Yes I do agree with you about pdf conversion. Maybe HP people have had done it and available internally somewhere. I don't know why they don't have them on their docs.hp.com website. I know they don't provide any support for these machines, but it shouldn't hurt them to keep the docs available at the site. Because even if someone call HP about the docs of these system, they would simply say not supported without even bothering to looks for docs somewhere internally as a courtesy to the customer.

Secondly, there is this interesting thing. Recently HP had a contest to reward the customers running an oldest HPUX machine. As a matter of fact, there are many systems like E/I class are in production and in other use even these days. So the credit goes to the admins who tried/trying hard to make them running without any support from HP not even docs!!