I stacked the trays together and re-measure its width and height and found them to be a bit taller than their respective drawings. It is because they have small dimples above and below their radio trays - just to keep a slight separation from their neighboring component. Once established, I re-marked and cut the radio stack hole onto my Instrumental Panel.

Here's a picture of the radio trays fitted to my radio frame structure. Note the side panel mounted against the horizontal rails? It will be trimmed some more after I have determined where the radio tray mounting holes and the venting holes are.

Unexpected Interference

The mounting holes for the radio trays are quite far forward to the IP, majority of them lined up to the foam core of the original glass IP. Here's a picture showing the unexpected interference. If you look close, you can see the front most holes are located at the foam core as well as the L bracket. Obviously, the foam core will not provide a firm footing for the radio trays. I need to make some changes that provides a better footing.

Here's what I did...

I removed a strip of foam (~1 1/4") on both sides of the radio tray, leaving the front layer of glass in tact. The three screw holes were the left over holes and will be filled later on.

Then I epoxy an aluminum strip against the glass for strength and stiffness.

Then I added a layer of BID over the aluminum strip and around the foam core, sealing the edges.

Add a wider angle strip (1 1/2") for the radio tray.

Radio tray structure re-installed. Note the side panels are further drilled and trimmed to match up with the radio tray holes from the manufacturers.

Final mounting of radio stack trays. Its a lot firmer and secure.