Ah yes I get you now, that sounds like a plan indeed.Oh.. I thought the batons were going to be inside the cabinets.
With regards to your second image. I am recommending that you pick up a new end panel and cut it so that it spans the width of your two brown lines (rad brackets). Lets call that part A. That end panel would be then screwed to the ends of the two units, however, because the wall juts out by 4 cm, your newly cut panel will be 4 cm away from the cabinets and require you to pack them out using off cuts from the rest of your newly purchased end panel. Two strips of end panel either side of the wall (parts B) plus 6mm packing pieces behind the cut to size part.
View attachment 218263
The advantage of the above is that you will then be able to screw the A/B combo from the inside of the cabinets (no visible screws when looking at A) and you will be able to screw through part A into the end of the wall (unfortunately two visible screws). You will now be distributing the weight/load of the rad throughout the cabinets and the wall.
When looked at from the side, yes you will see the A/B panel but it will be the same colour as the end of the units.
I hope that makes more sense.
I did find these ugly things which might be easier https://m.ebay.co.uk/itm/Adjustable...e&pageci=452ba79b-df72-4588-870a-224d943416e9
I must admit i’m not too fussed for looks as heat is all I require the most
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