Is it popping at all when you try to start it? I doubt it's the gas. I agree that is does go bad after a time, but I have pulled cars out of the garage after two years, and it started and ran fine. I have a 67 camaro that I am restoring (little by little) and it has the same gas in the tank for 5 years, and I can still start and move the car. Im not saying the gas is good, but it will still allow the engine to run, that's why Im saying I doubt that's the problem. Those parts that you mentioned that were recently installed, was that before storage, or after you took it out? I would lean towards spark and ignition, but I could be wrong. Check your msd connections, and make sure you're getting spark when cranking.