Clutch Installation, Mechanic wants double Options

[junhus69]

I bought a clutch kit for my 94 Celica ST from Gripforce.com for 113 dollars. I gave the clutch to my mechanic who was supposed to swap out the old one and put in the new one. When he took out the old one he didnt look to see if the 2 pressure plates the old one and the new one matched. He mounted the new clutch and put it back together. He went to start the car and the pressure plate which was to big was grinding against the bellhousing of the tranny. He lets the car sit there for 2 days without calling me or anything. Im in the process of studying for a chemistry exam so the car is not the first thing that is on my mind. I go to pick up the car and he tells me the problem. I get pissed and tell him that he should have called me when he had the car open, he didnt he just assumed and put everything back together. My uncle told him to fix it so he orderd the parts from toyota and the car i supposedly fixed. HE WANTS TO CHARGE ME DOUBLE FOR INSTALL!! I have talked to 3 technicians that i know and i talked to a toyota tech and they all said it was his f'ing fault for not checking the pressure plates
Should i pay him double
what is a reasonable price including the 185 dollar clutch kit.