I'm not sure the bolts are there to hold them on. They are actually more like plastic lugs. I tried to get the front ones off to get to the temp sensor for the FBH but gave up!
PS the gaffer tape was as a result of my daughter trying to move a skip with the car!!! She lost!
im about to put one on mine the instructions say double sided tape and screws also need proper cleaning agents for the body where the tape sticks and automotive glue in someparts as well