Hey Kman!, yes I'm quietly beavering away at this conventional cab design up in the sticky section. Just FYI, X Factor was the album of choice to listen to while I drew up these images.

Who knows, i may just build this myself!
I've been off work sick for a few days and so with a bit of time to progress this design project along. Before assembling the CP parts the additional front panel should be attached to the cab. Using two brace pieces matched to the length of the front panel, screw/ glue them on either side of the coin panel cut out.

Attach the decorative panel by driving screws from the outside of the cab through the (remember to countersink the screw holes) panel and the brace pieces.

Using the Visio CP cutting and rebating diagram attached at the end of this post, cut out the holes for buttons, joysticks and trackball. As I've mentioned before, my preferred method is to make a template from thin MDF first. Some people just print out the template, stick that onto MDF and then drill out each hole. Thin MDF is much easier to work with to get clean edges around button holes etc. Once you have the template use a flush trim bit and router to cut the actual CP panel out.

Again using the CP rebating guide diagram, route out the rebates for the joysticks and trackball. These controls will be mounted to the CP from the underside of the panel. Counter sunk machine screws embedded into the CP panel will hold them in place.

The CP back panel will need two rectangular holes cut out to allow fitting of controls and wiring. Note the three holes for mounting bolts through this panel and through the CP backing plate already fitted to the cab.

Use brace pieces inside the CP along the panel joins as shown. Glue and screw panels together in the same way we’ve been joining other panels on the cab. Any counter sunk screws will be filled over prior to vinyl wrapping the CP.

The CP backing plate will also need two rectangular holes cut out to allow wiring to pass through to the CP.

The CP is angled at 5 degrees. Using a sander or a rasp angle the edges of the CP Back and Front Panels (and the brace pieces) so that the CP top Panel sits flush at a 5 degreed tilt.
EDIT: Guess what I forgot here? Well rhetorical question, I forgot to include marking and drilling the holes for the screws to mount the joysticks & trackball
THEN Glue and screw down the CP Top Panel and the End Panels, making use of the brace pieces to screw into where available.

Here I'm showing the CP bolted to the cab using the three bolt holes (with the CP top removed for clarity).

Here is the view of the CP bolted into place from inside the cab.

Here's a slightly more realistic render to show what the assembled cab should look like so far.

Next i'll cover the remaining panels around the marquee, slot cutting for T-molding and some filling and finishing techniques prior to painting and vinyl wrapping the surfaces. Just below is the Visio file for the CP button holes and control rebates. If anyone prefers this as a CAD file PM me and I'll provide it.
EDIT: Note that the layer 0 in the Visio file can be scaled onto a larger page size for printing, just choose 1:1 scale and it will print out perfectly to full size scale on 2 x A3 sheets, I've tested this myself. No need for complex measuring just stick down the printout and route the CP panel, easy eh?
