Not a good idea to do that . The reverse gear beeper is there so you don't accidently select reverse when you want first gear or vice versa... as there is no interlock or gate barrier on the gear selector, so there is a real danger you could accidently select the wrong gear , hit the accelerator and fly off inthe wrong direction .
the parking sensor is simply to tell you how close to something you are .
NIgel G, August 2008