When I first got this car I made a check list of what did and didn't work. It had an alternator then and the light went out when I started the engine. Since all my resto work now the light is bright when I turn the key on and when I start the engine it stays on but not as bright. The Alt is putting out 15 volts and works so what could I have wrong. Have I left some part out? Please someone help if you can.