The bucking could be from the increased throttle response from the tune or the mods you did with your tune. Rapidly pressing and releasing the throttle to compensate for a new touchy throttle would cause that.
If your clutch is slipping, you'll notice the rpms shooting up but the car not moving as quickly as you would expect from the revs (more noise, less acceleration). You'll notice it most if you put your foot down hard, are going up hill, are in a higher gear, or a combination of those. Plus, you will definitely smell it when you get out of the car
Grabber orange is NOT yellow!!!