Back bumper on 300Tdi

I need to remove the back bumper from my 1998 two door. Any hidden nuts/ bolts I should be aware of? The lip under the back door needs a weld (previous owner kindly filled it and painted over and it turned into a nice hole today). Does anyone know if the plastic flap that extends out from below the top surface of the bumper can come off without taking the whole thing apart or am I looking at whipping the whole unit off?

only 2 bolts hold the rear bumper on - 17mm and the rear light bulb holders/wires , rear plastic trim has screws that will be revealed once bumper is removed

Thanks, may seem obvious but where are the two bolts lurking? Without going properly underneath I can only see the 13mm ones at either end which hold side bits on.

follow the chassis sides backwards and you will find them - can be awkward, you will need a socket to undo

Chances are that the hole you found won't be the only problem.

You may need to replace one or both chassis mounts. When I had this work done on my D1 they had to undo both chassis mounts and lift the body up a few inches to get to the areas. I took the opportunity to change the bumper over for one that hadn't rusted to within an inch of its life.

More than likely but I'll find out once it's off! In any event it's better now than at MOT time or worse.