I did my '91 350SDL in the same manner ... wish I had spent more time cleaning, though. I just pulled edges back and tried to direct the adhesive spray where it needed to go ... I had some detriorating foam mix with the adhesive and form a slurry ...
Bottom line - I wish someone made the right kind of low viscocity adhesive in a brushable format ... would have been easier, I think.
The photo series is a GREAT way to explain projects - I am going to do the ecamera thing soon and will start taking photos that not only will help me remember where part "a" attaches to assembly "b," but will allow me to share lessons learned more effectively.
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg