I'll see what I can do about some tool tray dimensions, but it's very tricky to convert into a workable template.
The first thing to do is to get a sheet of thin plywood exactly the size of that which covers the standard tooltray. I can't recall the thickness but it's around 1/8th. Then you need to cut a rectangular hole in this sheet, but leaving enough overlap for the sides to fit in the well. Then I located and drilled the four holes in the existing location to reuse the original holes in the frame.
On my Roadster on the nearside was a small 'extra' block of wood of indeterminate purpose which had to be worked round. Now here's the hard part. The diff sits in the forward part of the well, and my axle has a brake pipe on the nearside of the diff. Space must be allowed for suspension compression, and so that the brake pipe doesn't touch, rub or chafe. This means that the available depth varies from an inch or so over the diff, and the raised section is just visible in the photo. The rest is between two and four inches. The maximum depth of four inches is on the offside, so left side of the photo. The piece of wood cut out of the initial piece can be used for the 'floor' but must be cut into sections according to available depth. Since wood doesn't curve well, this means quite a few right angle joins. It's very important to frame the sections with as small a cross section wood as possible, and screw & glue because you don't want it to fall apart when loaded. I always have offcuts of wood in the garage roof, being a big DIYer, so apart from the ply, used what was there already. I left the tray a few days to harden - which makes it rigid, then painted it satin black and applied Tectyl wax to the underside. I used right angle plastic finisher around the hole because my woodworking is rustic to look at......
I had one incident on the first long run when the diff caught a small corner when I bottomed the suspension 'at speed'. There was a loud crack,
which, when investigated showed that a corner of the plywood which could have been rounded off had been chopped off cleanly. So a bit more sanding, and a squirt of paint/Tectyl and all was well. In order to refit the original ply cover it's necessary to chamfer the wood so the it can locate further under the two metal keeps with the extra thickness of the new ply.
I'm now psyched up for a session in the garage tomorrow, so I'm hoping to get on with the front mudflaps, and the extra badge. I'm also working on a brake lamp relay and pedal switch, and a spare wheel securing clamp, because although I'm assured that there isn't a problem, I'd be happier with more of a physical deterrent. My Mk1 stainless protector failed miserably at 60% complete due to drills past their best. Very annoying but a good learning curve. Stainless is very hard to work and drill accurately.
Finally, here's a funny thing. I noticed tonight that the wire spokes around the valve are not in alignment with the rest. The two crossover spokes cross closer to the hub, and the two which are almost parallel around the wheel diverge more noticeably. It's very subtle and very clever. If you have a Roadster with offset wires, have a close look.
Time for bed.
