Maybe a bit overkill, but i'd rather slightly overbuild it than go too light. The top rail (which took most of a day to design and make, and still need the ends trimming down) was added to replace the bolt-on, metal bumper, and the lower replace the mangled, old cross-member. This is all going to be covered by a fibreglass bumper.
Edit: A bit more detail on the fabrication of the top horizontal rail: it started off as a bit of 60x40x2mm box, which I slit and re-welded to make the narrower bit, to allow for an extra, lower grille. As careful as i was, the heat from this welding distorted the section, putting a fairly uniform bend in it. To fix This, I had to make perpendicular slits along the bent section, and re-weld them, whilst the whole thing was clamped to a stiff section of heavy steel pipe. It was a lot more work than it needed to be, but happy with the finished result. Nice and straight now. Then used the same technique to taper the ends in to the same angle as the headlight surrounds. Because the box is stiffer in this plane, it didn't bend s noticeable amount .
Anyone with some welding experience know how I could have avoided the bend?