Posted on request on Einstein:

Below is a picture of the digital thermometer I installed.

The product was found at Wal-Mart, near household electrical do-dads.

AcuRite P/N 00888W, US$9.97

The thermometer features:

°F/°C
In/Out (although it's changed by a stiff switch on the side)
Bright green LED backlight that stays on a few seconds after pressed
Min/Max temp recall.
Sticky velcro tape set for mounting unit.
Sticky foam tape for mounting the sensor.

I belive it matches the Element interior quite well.

The sensor is on a wire of perfect length (for the way I routed it).

The only panel I had to pull was the subwoofer frame, which was easy (two pop-in rivets on the side. If you have a carpet, I recommend taking it out beforehand, otherwise it's a little difficult to put back.

Routing:
Behind thermometer,
through seam where subwoofer frame meets dash panel,
behind subwoofer frame,
under glove box hinges,
through lower edge of glove box frame/ in front of inner door weatherstripping,
behind rubber-encapsulated door wire bundle,
in front of rounded painted metal protrusion above wire bundle
under little painted triangle between side mirror and windshield
under hood hinge plastic cover
along windshield washer hose, using clips
beside P/S and coolant resovoirs,
along headlight bulb wires,
beside radiator,
then finally I used the provided double-sided tape to attach the sensor under the center dividing bar in the lower grill opening.

As usual with any automotive thermometer, you have to be moving along in the airflow for a couple minutes before the reading becomes accurate. Also, keep in mind that on a hot summer day it will read several degrees higher than the air temperature because of the heat coming off the pavement.

Einstein has attached this image:

http://members.rogers.com/kjcelement/images/digitherm.jpg

Well I removed this thermometer because the Wayfinder has one built in.

But I do have some ADVICE!

I used the "hook" piece of velcro on the device, and the "loop" (cloth) side on the subwoofer cover. The adhesive on the cloth-side would let go on a hot day, and the thermometer would fall, dangling by the cord..

To fix the problem, I bought fresh Velcro on a roll. I took the cloth side and cut a long strip. The top of the strip I tucked around the edge of the subwoofer cover, so that if the sticky stuff let go in the heat, the velcro would stay in place and the thermometer would not fall down. This worked pretty good, even though the cloth let go from the plastic on a hot day, it would still support the thermometer from being "jammed" between the subwoofer cover and the rest of the dash.