Thanks to Cieka

After doing some work on my PTT, i put this DIY together to help others replace their own shocks. 
Ended up replacing both front shocks. Then, one of replaced shocks was not working.
Once I figured that out (info about how to diagnose is in the air suspension info thread),
company overnighted another replacement (I pre paid, and they refund money afterwards -takes about 2 weeks after they get shock back).
Doing first shock replacement took about 4 hours with pics, breaks, etc.
Doing subsequent shock replacements (other side and replace of defective shock), took about 1.5 hrs including wheel attach.

My advice, do not be intimidated. Not difficult. Keep your eyes on the prize – new car with new suspension working perfect.
Then do the job. You will enjoy lots of money saved.
People take their cars to dealer to have this done, have posted bills of $9000 plus tax for replacing front air shocks.

My price for doing this myself:
– $375 for driver shock (pre paid 525, got refund $150 on used core charge)
– $375 for passenger shock (again pre paid 525 and got 10 back after I sent old core back)
– $120 for valve block (decided to replace as Durametric does not have capability to test individual valves to see which is broken or not.
– About 12 hours of time spread over few days (you can do the whole thing in one weekend no problem – one day). Of course,
my time included taking pics, organizing things, doing troubleshooting so I can have proper write up about air suspension (separate thread – search for air suspension info), etc.
Your time will be likely about 8 to 10 hours max, since you already have this all laid out to follow.

Money wise, I spent $870. Compared to $9000 bill, that is $8,130 SAVINGS!!! – Before tax!
Think what you can do with that money!! Of course, if you feel you have too much after DIY, you can paypal me some – I will not complain.

REPLACEMENT PARTS I USED:
Rebuild Master Tech shocks. Look online, make sure you get the proper year and model and side you need.
Not sure if there are other vendors doing this. Cayennes used to have Arnott, but checking I did not see any Panamera air shocks.

OTHER INFO:
While you are doing this work, it is good to think ahead, if you need any other work that will save lots of time, if done at same time as air shock replacement.
– Upper control arms (see my DIY) – if you have clunking over bumps, these are likely culprits
– Lower control arms (see my DIY) – if you have clunking these can be reason too
– Sway bar bushings – if you have squeaking coming from car over bumps these are likely the reason. You can lube them to see if helps, but once all this stuff is being worked on, bushings are just a small addition
– Other brake jobs, etc in the area.

Do not rush, take time to do correctly. Hope this helps you fine folks. Follow each pic as it is numbered. Last pic has hardware torque info.