Gusset
The gusset is the fitting for the steering wheel mounted hand break. They only made it for Lt hand drive vehicles latterly as I would imagine. I had a couple of Rt hand drive F4 vans that was probably built early seventies, I ran them in the early eighties, and they both had column mounted hand brakes. At that time the front brakes were drums, not discs, and the handbrake acted on the front wheels, by a totally different set up. I now have a French Lt hand dr F4, with disc brakes,which has a column mounted hand brake acting on the rear wheels, by the means of a lever system mounted on the rear of the chassis, (there is a flange protruding from the centre of the rearmost trailing edge of the main body of all later chassis, containing three bolt holes). The F4 body, I'm mounting on an English GTL chassis. I am going to have to make a Rt hand version of this gusset, as they don't make a hand brake cable that will stretch across to the present gusset. Having used, and still am using on my Spanish F6 van, a column mounted hand brake system, I just had to make the effort to incorporate the system in my present project.
It's interesting to note that the system in Spain is slightly different to the system in France. The French system uses a single cable from the handbrake lever, and then two further cables running from the lever system to either brake drum. My Spanish F6, however has the single cable pulling on a pulley, with a single cable running between both drums. I only found out last month that the means of adjustment for the handbrake was to tie a knot in the front cable prior to its attachment to the pulley, as a means of shortening it. I need to tie another knot in it when I'm next there. It requires 6 monthly MOT's in Spain, as I was warned last time that the hand brake needs adjusting.
The two bolts, as far as I can see, having looked at them on my own chassis, do nothing more than anchor the front end of the folded steel tunnel which lies underneath and runs down the middle of the floor.The rear end is spot welded to the floor, so there is no point in removing them. It is not the only plate piece that seems to be attached both by weld and bolt. The full purpose of the tunnel I'm not sure about, but the floor mounted hand brake cables exit from its rear.