I have a 2008 LS manual 2.2 coupe.

I notice that I was having a transmission fluid leak. I had replaced the slave cylinder but i may have pinched the seal when putting the housing back on lasted for about eight months. Instead of dealing it myself. I paid a shop but was later told by many that shop had plenty of bad reviews. Once I got the car back I checked underneath and noticed a build up of transmission fluid along the seem. And a friend of mine pointed out gasket maker also along the transmission. He mentioned there shouldn’t be any gasket on there. So instead of worrying what other errors they were going to do to my car. I had to do it myself again. I got the new slave cylinder and clutch disc and just about the remove the flywheel doesn’t look like it needs to be turned but I was having grinding issues and problems getting into fourth gear. At times I would just go from third gear to fifth gear thats how bad I couldn’t get it into fourth gear. I just need help and guidance on how to replace the fourth gear. Anyone who can help who has been in my shoes. Greatly appreciate it.