Help with convincing my dad to help me get a car?

[jack]

alright so i have 7500 bucks saved up because i worked last summer and i turn sixteen in march. i have been looking for a car and my best friends dad got a Mazda rx 8 touring and i fell in love with it. basically i started looking for one. i found one for 12000 and decided to try to convince me dad to help me get it. i have a got a summer job secured at discount tires and it pays good, i told me dad that if he got a 4500 dollar loan that i would give him the monthly payments, i would get a loan myself but a bank wouldnt give me one. so after all this im just asking if anyone knows any ways i could help convince him. he likes the car alot so that helps and really i would just be using him to pay the bank indirectly. so ya if you got any ideas that would help