My suggestion then, is to get some new double sided 3M tape for
the normal top edge of the spoiler.....stick that in place onto it,
then peel back about an inch as stated in my earlier post, and make
the 'pulling tags' ready for when you mount it.
Next, put some new 3M double sided tape onto the cleaned up face
of the plate that is now part of the spoiler.
Your only problem will come when you come to re-hang the spoiler....
as you will only get one chance, because if and when that plate touches
it will stick in place like the proverbial 'pooh to a blanket'.
So......what to do about that then, eh ?
Well, when you come to mount the spoiler, hook the end of the 'good'
part/side around the wing edge and hang the top lip of the spoiler on
to that side mounting plate....BUT....keep the 'bad' side held
slightly away.
Then...still holding the 'bad' side away from the front of the car, gently
twist that side down and towards you...and get a friend to manouvre or
fiddle the hooked end of the spoiler under the wing and then up the edge
to the correct point it should be.
Still keep as much pressure as possible on holding the 'bad' side with
that taped up plate away from touching.....you just need it apart by a
few thou of an inch really.
Anyway....with the 'bad' side's end of the spoiler now in place (but neither
side yet clamped up), get that same friend to then step back and 'eyeball'
the spoiler to confirm that it is more or less level ...and then go for it and
push the 'bad' side of the spoiler + taped plate onto the front wing.
To finish the job, pull on those 'tags' that you made/left earlier for
the tape to the top of the spoiler and press the top edge into contact,
then fit the end clamp blocks and tighten in place with their bolts.
Finally push into place and press in the centres of the long plastic
spreader rivets that go underneath...and that should be it.....job done !
