help me...power problem...please help!!!

ok so last week we re-sprayed the Nova (gsi look-a-like) in matt black so obviously a few things such as eadlights and battery were removed...

...now when i drive the car is fine except when i put on the headlights..this then causes the car to misfire continuously and eventually stall/turn off when at a stand still...

...any ideas...i fitted central locking with door popping solenoids as i have no handles or locks on the doors now...origionally this was linked to the earth terminal on the car and NOt on the battery and i thought that this was making the earthign o the car bad...i have swapped this around since but still have a problem...sometimes the dash lights come one whilst driving like the car is about to stall...but only whilst the lights are on when the lights are on...

...seems like so much power is being drained from soemwhere that there is not enough power for a spark from the distributor!

...any ideas? i work at halfords and have done a battery test which comes out fine...battery is only 4 months old!!

Could the alternator be shorting possibly? when lights are off the car runs perfect.

any ideas to try would be welcome...
...cannot drive at night at the moment!!! so rediculous!

thanks..

..Martin.

OK...

...on my second attempt i have noticed that the rear lights do not work at all..no brake lights, indicators, nothing!!!

any ideas?

have sorte the problem...not sure what i really did though!!

i just re-earthed the rear lights as the car wouldn't turn on without them plugged in?!?! then plugged the lights back in and it works...guess it was a dodgy earth?

Thanks to those who had a look at the post.

Martin.