Where can I get a diagram showing all aspects of the A/C System, including installation

I am in the process of installing a new A/C Compressor. I suspicion that somebody worked on this system before. I would like to know where all the o-rings go on the hose connections. I bought a kit which has load of rings and washers, Will I use all of these?I know there are grooves to accomodate them, but is that it? It seems the sealing of the system relies on, basically two o-rings per connection, again, is that it. Too, in the rear of the compressor, there are two cavities which I believe are low and high pressure ports. I know on my old one, the only thing that I had connected was the low side. I don't know which side is which. Am I missing something? I an old subscriber with a new e-mail address.