I just completed a 4 speed conversion , and now when i try to start car it turns over like the battery is dead. I had the battery load tested and charged twice, the altenator bench tested, the regulator(external), replaced, and now a new starter and seleniod. The cables are clean and tight. Nothing seems to solve the problem. After a charge it will start a few times but then turn over real slow with little power. The lites seem dim too. Is it possible the battery needs replacing even though it load tested ok?