Basically, all you need is some plastic, 2 hinges and some spray paint. The thing on the right is velcro straps, but I found I couldnt use them in the end.
Here is the cupholders before paint and hinge installation. To get to this stage I basically just measured out the compartment and drew it up on the plastic. You can get this cut out in less than 10 minutes at a workshop, or take 4 hours sanding, sawing and chiselling by hand like I did.
I used Tarzan Grip super glue to attach the hinge to the cupholder, and double stick padded tape from the hinge to the compartment. I tried to hot glue it, but either something is wrong with my glue sticks or the hinges REALLY doesn't like hot glue. If this doesnt hold, you may be forced to have to screw some holes in your compartment. I'm trying to avoid this.
And finally, the cup holders in action. Apologies for the dark photos, I took these in my dusty old dark garage.
