A touch kit is pretty simple to install IF you had the basic skill and knowledge to disassemble and reassemble your existing LCD.
To install a touch kit like my friend Mobile and Solid sells you would take appart the screen. The next step is to remove the LCD from the bezel. Next, you put the touch overlay inside the bezel and put the LCD back in on top of the overlay.
The touch screen becomes the meat in the sandwich. You use double sided 3M tape (the white kind) to affix the touch kit to the bezel and the foam creates a buffer between the bezel and touch kit to prevent false clicks from the bezel.
From there it's just putting things back together and plugging the touch kit USB cable into your PCs usb port and installing the drivers.
To be honest, the touch kit I installed in my screen has been better than the three Lilliput, Xenarc or DWW-700H screen I owned, hands down. Here is a thread about it:
2007 Mazda 3 Dash Screen looks OEM
I will be posting pictures soon.