Hi Gary,
I made my own a couple of years back and thought I'd posted here but as I can't find it now, I reckon it's my memory failing again. I'll go through the notes I made and post a full description, but for now these are the important bits.....
Brackets - the first PDF is what I made up, the second is a rubbing taken from the OEM bracket to show the angles, etc. This is on a TC chassis, I expect the others to be similar.
The original one is shown with approx dimensions. The replacement is much heavier and stronger. I ended up buying 60x40mm rectangular section with 2mm wall thickness. I bought one metre and there was a bit left over. The brackets are also made from rectangular section, I bought 80x40mm section, 4mm wall, half a metre this time.
Later on today I'll post up a PDF with the fabrication method and things I learned making it, it needs a few more photos adding to make things easier to understand.
cheers
Brian
Edit to add - PDF of method attached