[Zedn]

Sorry, just remebered your case is a bit different.

Is your car classed as an ICV or modified production?

Most kits have a couple of pieces of RHS or tube. You need to consider the whole picture though and not just the bars. Consider the load path in the event of a side impact. What you have linked may suit that car, but to other cars may be a lot of weight without improvement. In most cases the front of a car wont fit between the centre of the door and sill so the whole lot doesnt need to be filled in with metal. Also the hinge and latch are the weakest link so introducing more steel in the bars is no good if the striker plate of the door does not mount into solid enough steel.

My gallery has some pics of how it is done in my kit.