Now the GT won't start

[AndrewOst]

Hmmmm,

What have I done?

Still no luck with fuses but working on it.

Went to drive it to a mechanic to get roadworthy for registration and it won't start.  Battery totally stuffed. Tried to jump it off another battery and it will crank but very slowly.  Took out the dud battery and connected the other battery (not car but 120VA deep cycle) and the same thing, it will only turn over very slowly and just once. Also made a strange high pitched noise once and the driver's window went up and down a couple of times, resting half way up. Now OK and slide up properly when door closes.

New battery ordered and arriving next week.  The old battery was almost dead when it arrived and I did charge it.  Could I have stuffed the electrics?  Tested the fuses on the positive battery terminal and all zero ohms so OK.

Any ideas, or what to look for when I connect the new battery?  I'm getting nervous about this car.

Thanks

Andrew