That spring is the BUSBAR SPRING and yes it can kill you if you open the cover up without knowing how to properly release the pressure...Your BUSBAR spring came off the rod most likely caused by improper operation of the GCP...The BUSBAR spring and it's rod needs to be properly set up now and hopefully nothing is broken inside......You need to get the manuals for your Ferret...Get all the manuals..One main manual is
SCOUT CAR,FERRET,ALL MARKS USER HANDBOOK.....In that manual page 119 under Servicing-Gear Change Pedal you can find out more.......What country are you in ?
Joe in Black Hills USA