To repair the plastic tabs on the front grill i tried Plastex, you can find the website using Google, i found cheaper kits on e-bay though :)
First i used the moulding material to get the shape off a tab that was intact, you boil the material for a few mins and then mould it to the shape you want, it sets in seconds and you have a perfect mould.
Clean the area well with fine sandpaper to get good adhesion.
The mould in place, if your carefull you can even mould in the bolt hole.
You then use the pipette to apply the liquid and powder to the mould, this stuff smells strong so use in a ventilated area!
After about 20mins remove teh mould and you have a repaired tab, it can also be used to repair cracked or broken peices.
I shaved the rough edges with a razor blade, after using the product a few times you can get quite neat finishes first time, i made teh mistake of thinking it would be easy sandable, but it sets like iron, so get it as good as you can first time.
A quick spray over with matt black and the grills are like new, the product is strong and adheres well to the existing plastic.