Smoothing number plate recess?

[mark_airey]

This topic always results in an argument of the "correct" way to do it in my experience and somebody always claims to know better when IMO there are different ways of getting the same result none of which are really wrong, obviously using just P38 filler won't go well as it will most likely end with cracks or shrinking due to the massive area that is the plate recess.

I'm not really going to add anything useful as my smoothed plate bumper is still sat in primer in my workshop so I have no Idea how it will hold up to being on the car but we will see! My current bumper has the lower line smoothed out which was done by using coarse sandpaper and a knife to score it for a good key and then using P40 fiberglass filler just shy of the finished surface level (believe me you will regret it if you put too much on as its an absolute shite to sand back again) and then a skim of P38 filler over the top to get the shape and smooth finish for paint! it held up fine for 2 years until I hit something fury and animal like the other month and destroyed the entire bumper.

I'm not sure how well it will hold up with the plate recess done like this though as its a much bigger area so I'm not about to dish out advice on that until I know!

** I haven't re-read this so it might make no sense at all **