well Andy don't laugh now. Next time you do the plastic say in a couple of weeks follow eactly what you have already done

BUT

when it comes to applying the Auto Glym product bumper trim stuff

either

use a hair dryer when putting the stuff on. I Know what your thinking

OR

put the bottle of Auto Glym in to really hot water so the product is hot when your applying.

You will be amazed at the finish just humour me on this one and try it.