The Huf sensors do not require any tools and locate on their own 100%, I may have found the clue you need, Ive found very commonly with BMW, who uses the same style of sensors, when owners drive the vehicle without a set for an extended period of time the cars system locks out the TPMS feature. With those vehicles the entire system needs to be reset. Sometimes this can be done by disconnecting the battery for about 15 min's and the car will do a complete restart. I'm not sure with Ferrari though if there are any other issues with ECU or other systems but I would assume it would not be a problem.