I recently bought a 76 Arrow, Automatic 4g32. I did a complete tune up today. It had very old gas and had been sitting for some time. Changed out gas, plugs, wires, filters, oil, dis cap and rotor. Fires fine, idles good in park, but as soon as you put it into drive it bogs way down to the point where if you dont keep your foot on the gas it stalls. Anyone have any idea what maybe causing this. Thanks for the help!