1 - Leave the paper of the UTH ON. Tape it with paper side to the glass on the bottom of the tank.

2 - The probe you tape in place is the thermoSTAT probe against the UTH on the outside of the tank.
You do NOT tape the thermoMETER probe, since it's inside the tank. Instead, lay that probe against the glass right over the UTH and keep it in place with the substrate and the warm side hide.

Hope that clears things up for you.