VS Commodore won't start after starter motor replacement. HELP

[TractorGuy19]

Hi guys I've has this issue bugging me for a while but haven't had motivation as this isn't a daily car. I own a 96' VS Commodore wagon S2 and have been facing this issue of it not starting. This issue became present after trying to put the car into drive and the automatic gearbox slipping leading the car to stall. I had to repeatedly start the car as it kept stalling whenever I tried to take off. Eventually it wouldn't start again and was acting as if the starter motor was stuck or dead. I attempted hitting the starter motor and swapping fuses but to no success. it seemed as though the starter was engaging but couldn't carry the power to spin it up resulting in a loud click and seeing the pulleys move ever so slightly. The car then sat for a couple months and a couple weeks back I ordered a brand new starter motor for it and proceeded to fit it. I then faced the same issue when trying to jump start the car but after a couple key turns and swearing at the car I got a half crank... twice. It has then been showing the same symptoms as before and still has not started. Some other info is that the gearbox is totally rooted, it wouldn't shift to overdrive or first gear and when it shifted up from second to third it wouldn't shift back down even when manually selecting.

-loud click when trying to start and pulleys seen slightly moving
-replaced starter motor
-swapped fuses
-Automatic gearbox slips and stalls
-Won't crank... 90% of the time and when it does only half way and stops

It acts as though the gearbox is stuck to the engine, I jacked the rear wheels up and tried to start the car but with no success and the wheels staying stationary.

If anyone knows anything on what could get my car running again that would be much appreciated.
(If I can get the car running I will be buying a replacement gearbox)

 

[LXCHEV]

I'd start with a very thorough check of your wiring, including battery terminal connections etc... 9 times out of 10 it's the super simple things.

 

[lout]

check the battery condition first
remove spark plugs as it may be hydrolocked
then attempt to turn over with socket on crank bolt
then attempt to crank with starter motor
then post back with what you found