I have a 1984 Mustang Predator convertible, GT 302. Under the hood, driver's side, the plate states: GT302, SFM 4S 107, Modified by Solomon American, Inc., Topeka, KS. It has 80,000 miles on it. My brother purchased the car in 1987, while living in Kansas City, drove it afew years, & then bought something else. The car was garage stored for about the last 15 years. I've been storing it for him in my garage for the last 4 years, & drive it occasionally around the block. He has no interest in restoring it & wants me to buy it from him. We have no idea what it's worth..help! I don't know anything about cars, but love buzzing around in it & would like to have some restoration done. Would this be a wise investment?