240 with touchscreen

[vincentfox]

Wondering if anyone has tried adding a touchscreen overlay to a 240?

I have a somewhat beat-up 240 I use for in-car navigation with DeLorme Street Atlas. I keep thinking how useful it would be if I could just touch the screen to recenter where I want, perhaps a few other simple functions. All the overlay kits I see are for 12-14 inch screens, not sure how this would work with the 10.4-inch screen on the 240?