In this weather, building an extra radiator seems like a really good idea !
On the 165DS this is assembled as a separate module and then attached to the bonnet. Construction starts simply enough with the sides and top being wrapped around the front. A pair of half etch sections in the corners to make the bends easier.
The grill bars are laminated from two parts with a bit of solder around the edge. Then the mesh is fitted from inside, I had to trim the top a little to get it to fit. Then the bars are fitted from the outside - and the aren't as wonky as the photo appears to show, or at least they aren't when I check them with number one eyeball or the engineers square.
The steps are fiddly but work very well. Two bends in a tiny bit of brass (thank goodness for square ended pliers) produce the tread which hooks over the outside edge and fixes with a blob of solder inside. Then a sliver of half etch is bend and fitted around the inside. I'll be honest I thought this was going to find itself ignored as you wouldn't miss it, but bending the metal around a small screwdriver allowed it to clip to the tread/back part.
Finally the outside corners were given a little rounding with a file. Not too much, there isn't that much meat in the metal !