This is a very nice 6.9, a California car from a prominent collection with 75K miles on the clock. Its factory paint is in amazing condition and the all-original interior is to die for.
The undercarriage, however, never received the attention it deserved, so we treated the car to a full dry ice treatment with follow-up detailing of undercarriage and engine compartment.

These photos show the undercarriage before cleaning.

After dry ice blasting removed the gunk, the car showed surface corrosion on driveshaft, various suspension and exhaust system parts -- quite common on a car that's been on the road for 44 years.
We removed this chemically with Fertan as well as manually, without disturbing factory markings and silk screenings.

After the effected areas were free of surface rust, we sympathetically by-painted them for an original looking appearance.

Thes following photos show the finished undercarrage in more detail.
Note that we preserved the factory markings.

This was a challenging car to do, but in the end it was certainly worth it and money well spent, given that our undercarriage and engine detail elevated it from a nice driver to a portfolio car.