Wreckfest's upgrades and cars are locked away behind career progress - however, I have unlocked EVERYTHING and have made it available for you all to use. The files are available as an archive over on the FTP: /_Misc/wreckfest craig save.rar. *NOTE THAT THIS NEXT STEP HAS CHANGED FROM BEFORE* Add it to your documents folder at documents/my games/wreckfest/some random numbers, it should unlock all cars, and all max upgrades for them, while still having enough money to personalise your cars. It will also make them a wonderful green.
In addition, @cosmo has created a new RlyR AI names file. This can be found on the workshop here.
This post will continue to be updated.