I did this process to my 85 GL about 3 mos. ago and it still shines  and
the rain water is still beading real good.
I used a 3-M product, called Finesse, and it does reguire a buffer, with
a sponge pad, but it works very fast in the removal of all of the
oxidized paint.
This Finesse, has no abrasives what so ever, and is easy to use. I don't
know how it works, but it cleans the paint nice, and it takes out any
swirl marks and scratches quick.
You would have to be King Kong on the buffer to burn through the paint.
This took me all of 45 minutes to do, and then I applied "Rain X" wax,
which I have been usng on my BMW for a couple of years, and seems to be
a very long lasting wax.

Happy Cleaning,

Terry