So now my armrest is finally installed, and I've modified the cup holders after being inspired by Jeff Bipes' method (thanks for the wonderful idea Jeff!!)
Here's the quick how-to of the install:
1. First I'm going to assume that the armrest is already installed with the tunnel cover off, as shown below:
The removal of the cup holders on the stock tunnel cover, as well as the installation of the armrest in the tunnel, is very well explained by the instructions provided with the Design Parts armrest, so I won't spend any time on this..
2. Here are the cup holders still attached to the tunnel cover:
3. To disassemble the cup holder piece from the tunner cover itself, remove the two dimpled aluminum covers - they can easily come off with your nails, or if you don't have any, a small flat-head screwdriver:
4. Removing the dimpled aluminum covers reveals a screw on one side, which is held by a nut on the other side. Remove the screw using a T15 bit:
5. Now you can see the mechanics of the rubber "flaps" that hold down your cups or glasses - it's just one piece with two ends, kept under tension by a spring:
6. After removing the rubber flap piece and the spring, you can see the screw that holds the cupholders down to the tunnel cover:
Take that screw out (again with a T15 bit), while careful not to lose the washer as well.
7. Now in order to know where to cut, tape off the ends of the aluminum rails and the side of the plastic base you want to remove (either side if fine, as the cupholders are symetrical) with masking tape or electric tape:
8. To make the cutting job easier, remove the vertical center plastic piece off by twisting in the direction shown, while pushing down on the cupholder base to free it from the aluminum rails:
9. I first cut the base off to give more room for the aluminum rail, which are much stronger hence harder to cut:
Note that screw to the left of the following picture, on the aluminum rim - it holds the plastic base and the two aluminum rails together:
10. Now to the actual cutting of the aluminum - I used a circular blade to make the job quick & easy, but it still took a lot of dexterity to cut at the right place:
11. To smoothen the ends, I used a dremel tool with a fine drum sander bit:
12. Unfortunately the rubber flap cannot be cut in half, as the spring would lose its counter-part to load tension on the other flap which we will end up using. Instead, the flap that will be unused must be trimmed a bit to fit between the arms of the armrest (sounds funny doesn't it).
Here's where to cut:
and here's the flap after it was cut:
13. Now on to the final mutilation of the day: set the cupholder (note the lack of "s" now..) on the tunnel cover. You have to choices: cut the original tunnel cover so that it fits around the arms of the armrest (I know, I know..) or make 2 little holes in the tunnel cover provided the armrest to screw the cupholder in it. I chose the latter option, as I thought making 2 U-shaped cuts in the stock tunnel cover would be more painful than just drilling two holes..
To do that, place the covers side-by-side (vertically then horizontally) to get an exact duplicate of the position of the holes, and drill away:
14. Under the original tunnel cover, you'll notice a rectangular-shaped metal piece with a drilled hole in it. You'll need to "steal" that piece (it's lightly glued on, so just pry it off gently) and place it under your new tunnel cover:
15. Now everything needs to be put back together. Replace the vertical plastic center piece you took out in step 8 over the cupholder's base and between the aluminum rails, insert the screw and its washer you took out during step 4 back in the vertical center piece, guide it through the hole and into the rectangular metal piece on the inside of the tunnel cover, re-assemble the spring and rubber flap (keeping in mind which end goes where) over the vertical center piece, slide the screw you took out in step 4 through the aluminum rails and vertical piece's holes and screw it into its nut, and replace the dimpled aluminum covers you took out in step 3:
16. Finally, take your new "chef-d'oeuvre" (masterpiece) and snap it under the armrest!