These are my additions to this thread. I had some questions and
made up my own answers.(I take no responsibility for errors
on your end). Hate that part. This a Bimmian M-tech Spoiler.
Prep the glass with your usual window cleaner and follow that with
two cleanings with pure Alcohol.
The main thing to remember is the dry fit
before your final attachment. Either one or both of the ends will
always stick up with the dry fit. When you place the 3m double
sided tape, leave a blank area from the center at least 3 to 4
inches both sides of center. About 6 to 8 inches overall.
Only attach the spoiler to the glass, the 3m tape is all you need,
no glue or adhesive needed. Attach the tape to the raised areas
only in the middle underside of the spoiler running from end to end,
and the short sides.The peripheral raised areas are to guide you to
the edges over the rubber trim. You don't need tape on the rubber trim.
Place the spoiler to the roof rubber trim first and eyeball an even split
to both ends at the rubber trim and go for it. Once it is down, that
is usually it. I didn't try to pull it off and got my line up the first time
as above. Lucky.
Once the spoiler is down it is time for the pressure. You will need
several heavy books to use as weights. Concentrate double weight
on the ends and single weight to the mid areas. Place a thick blanket
first with the slack over the trunk lid. Place the books and pull the
slack of the blanket over the books to the roof to hold the books in place.
I left this on from noon until the next morning and the very left end was
still slightly loose. That was ok, I drove it to work and it never moved.
I placed double the books that night and the next morning the left end was down solid and never moved again. Now some pics:
Spoiler with tape in place:
Before:
With the books and the blanket:
After pics:
