My door bars were quite 1970 standard and didn't inspire a lot of confidence in me in the possibility of a prang. I added 2 x 5/16 flat to them and the engineer was happy enough with my description of the work and style used. The striker plates are bolted through to some 1/2 inch metal and then a leg extends off that block through to the chassis. The weakest link is the bolts holding the striker plate and lock assembly, but that is deemed acceptable it seems.
No doubt my effort isn't as pretty or strong as what others have achieved but it gives me more peace of mind.
