65 valiant electrical problemos

gents,
i've got a strange issue that i'm hoping someone else has experienced. i had the car on stands for a couple weeks and when i took it down it woudn't start. i figure the battery just died so i charged it, got it tested (good) and it still won't start. just a click on key turn, then nothing on subsequent key turns. so i hooked up jumper cables and jumped it. after 5 minutes connected to my truck it started. i let it idle for a few minutes but once i touched the gas it stalled. couldn't get it to start again even with jumpers. replaced the voltage regulator and ballast, still nothing, not even a click on the key turn. oil like comes and goes and the dome light comes and goes. the dome bulb filament goes from bright to dead to barely glowing, back to dead, etc.. at one point while my charger was hooked up, the dome light was very bright but when i pushed the brake pedal everything went black.. plus i could hear my battery charger kicking off and back on. any thoughts would be helpful.

thanks in advance, guys.