Intsallation :

To install the car go to :
Grand theft Auto V / update / x64 / dlcpacks / patchday1ng / dlc.rpf / x64 / levels / gta5 / vehicles.rpf
and replace "rapidgt.yft" "rapidgt.ytd" "rapidgt_hi.yft"

To install the tunning parts go to :
Grand theft Auto V / x64i.rpf / levels / gta5 / vehiclemods / rapidgt_mods.rpf
And drop the files