I believe the sensor is in the dash 86-89, earlier cars have it by the mirror.
The pic is from my 87.
Re the condenser, I don't want to modify the vent in a factory 505 car at all, that's my only point. I'm sure anything can be made to fit. I still think the pass side front is the best option.

I'm installing a 11 x 20 condenser in the air dam in front of my 935 oil cooler with two 10" fans. In fabricating a new evaporator unit that mounts all in the trunk behind the dash. I'll post results when I'm fitting everything. It will have heat as well using engine oil. I'm doing this because I have none of the original A/C parts and I want Artic temps in my car. The new evaporator is rated at 14,000 BTU's A/C, 12,000 BTU's of heat and has 290 CFM fan rating. While this will more than likely work well enough to hang meat in my car it would not be practical for one not wanting to cut any sheet metal from their car.

GJF,
Very interested in your project. Especially in the engine oil heater concept.
You probably then will also be redesigning the hapless user-befuddling control system on the dash?

Going to try setting up effective and yet clean, simple controls.... I am just waiting on the evaporator. I will start a new tread and not, take anything away from this post. I have seen in person and heard many satisfied customers with the upgrades listed in this very thread. gskrken seems very happy with his results, and since his car is using the factory A/C configuration having low 20 degree temps out of the ducts says it all. Great Job!!!

Would like to add to this thread..for those folks who did this install with just a jack and jackstands...HUGE KUDOS!!!!!

I just did this install with a MaxJax and it was tedious(and dirty). Though I must admit it was kind of fun...like bungee jumping...doing it once is all the fun one needs. Took it Charlie Griffith for the Vacuum and AC Charge. Charlie hepled me out with my compressor(as I could not remove the Woodruff key out). As the day move forward he got the car all charged up. Overall it was a fun and educational day for me. For anyone considering this upgrade...it is money well spent. The parts and customer service is second to none. Charlie went above and beyond for me(as he seems to do with all his customers). I really appreciate that.

Special thanks to Ken(OP of this thread) for a great write up and the support I needed to dive into this upgrade.

Can you send me the link to the details of this installation?
How well do the AC and the heater work?

baloo try this site Griffiths Technical Inc,Porsche Air Conditioning,Posche a/c upgrades,Porsche ac upadates,Porsche air conditioning upgrades,Porsche air conditioning updates,Porsche barrier hoses,Porsche compressors,Porsche condensers,Porsche condensors,Porsche receiv or call Charlie..he can help you the most.

I did this over the winter. I didn't do any of the extra condenser s though. It took me a long time but I'm pretty slow at this stuff. It is a lot of work but not particularly difficult. I wasted about 5 hours figuring out the blower fuse in my car wasn't blown but wasn't making a full connection either.

I have owned my car for more than half my life and much of that time I have lived in the heat. It was a sureal experience driving it with the windows up in the cool cabin

GJF,
I'm really interested in the engine-oil heater aspect of the evaporator. Did you complete the project?
Did you use a separate oil pump to transit the engine oil?
Thanks.