I up-graded mine with the Classic Auto Air system. I think their Porsche distribution division is in Austin or near there. I think the Griffiths stuff is better, but I wanted a turn key kit. I have nothing bad to say about Classic other than the instructions were lacking. You need to be able to figure out thinks on your own. Some brackets and routing will need slight modifications to fit.
There is a thread by HotEuro where he installed AC in a non-AC car that will help you. I'll try to find it.
Found It
Retroair complete system in my non a/c car
Edit.
Ok this is weird. Looking at my link from Tapatalk it shows a wiring issue question. When I click the link it’s the correct AC link I posted.
Anyone else seeing this??