Features:
-Tuning Options
-HQ Interior, Trunk, and Engine Bay
-Doorsills
-Working DRLs and Turn Signals
-Dials
-Hands On Steeringwheel
-HQ Mirrors
-Dirtmapping
-Breakable Glass
-Animated Engine & Exhaust

Tuning Options
-3LT Bumper, 2SS Bumper, and ZL1 Bumper
-3LT Wing, 2SS Wing, ZL1 Wing, and Forza Wing
-3LT Hood, ZL1 Hood, and Carbon ZL1 Hood
-Widebody Kit
-Rollcage
-Carbon Fibre Roof

SP Instructions
First, go to gta5 / mods / update / x64 / dlcpacks
Make a new folder, title it "3lt", and drag dlc.rpf into the folder.
Then, go to gta5 / mods / update / update.rpf / common / data
Edit dlclist.xml, add "dlcpacks:\3lt\" above ""
Make sure to save.

Credits
Model: Gamemodels.ru & Forza Horizon
Conversion by me.