I've also made these changes in my PLR file (thanks to the guys over in the HistorX club)
To make a pit stop as smooth as possible it is recommended to map the keys you want to use to navigate through the pitstop menu or look at the default keys that are set, it is also recommended to modify your PLR file the following way:
[ Game Options ]
Relative Fuel Strategy="1" // Show how much fuel to ADD, rather than how much TOTAL fuel to fill the tank up to
Smart Pitcrew="0" // Pitcrew does things even if you mistakenly forgot to ask (one example is changing a damaged tire) Change from 1 to 0
Automatic Pit Menu="4" // brings up pit menu automatically: 0=disabled, 1=upon pit ENTRY, change cockpit menu but do not bring up HUD, 2=pit ENTRY->cockpit & HUD, 3=pit REQUEST->cockpit menu only, 4=pit REQUEST->cockpit & HUD
Miscellaneous="0"