I finally managed to get it out! Took a piece of wood and hammered the bolt down with a plastic pallet a couple of times. After that I just put the wheel my legs and shifted left and right with the handle bars. It did end up making some loud squeaky noises but after a couple more turns back and forth while pulling up, I managed to get the stem out. Everything has now been removed from the frame! Time to start cleaning and greasing everything. Thanks for the help.

Also, does anybody have any suggestions for cleaners for specific parts? Since this is my first time cleaning and overhauling a bike completely. Citrus degreaser on everything?