Reptile tanks that have a sliding screen top will have little tabs you can pop out at the top but you wont have any cords going from inside the tank to the outside.
The thermometer we recommend. The small Weather station at walmart, takes AA batteries. The unit itself stays in the tank (like it shows in a couple pics in those threads I gave you). The probe stays in the tank on the other side (hot side) so no wires or cords need to come out of the top of the tank.
The UTH is on the outside and the thermostat which the UTH plugs into is outside the tank. Its probe will be taped to the bottom of the UTH outside the tank (under neath it). Just be sure to use those little plastic feet that come with the UTH to raise the tank up a little. Or you can pick up a 4 pack of furniture riser discs (floor protectors). They are near the therms at walmart. A isle or 2 down. They just look like small round discs or square. Plastic and a little flat. I have used these under the 4 corners or a tank before as well.
Actually we have lots of Canadian members here. I bet tomorrow you will get some more advice on what you can do if you still have questions.