Welcome to the group, John, and congratulations on your purchase.
Regarding the codes on the paint plate, looking these up in the technical manual will be a good starting exercise for you. Click on “Technical Manual” at the top of the page. Scroll down and find “Data cards and color codes”. Click there and scroll down to find “Option codes”. You will find the code definitions there. The codes on the data plate are only a few of the codes that apply to your car.
If your friend supplied manuals and other paperwork to you with the car you may find a copy of the car’s data card among the papers. The data card will provide you with all the codes. You can read up on the data card in the Technical Manual. If you did not get a copy of this card, similar in looks to an old IBM card, you can obtain a copy from the Classic Center - - - for a fat fee!
I am sure some members in the Washington area will suggest quality mechanics in your area.
For the air conditioning matter. Try the “Search Function”, the button next to Technical Manual at the top of the page. You will find a lot of discussion on the subject. When you get into it in detail, post your questions here on the forum.
Again, welcome to the forum.
PS.
I didn’t get invited to Washington, but I was a great fan of, W.