I had to take the transmission apart on my Poulan Pro last summer, it is the same as the Husqvarna. Some water had gotten inside mine and the shifter had frozen up, so a gasket was the only part I needed. A little tip, every video I watched they took both wheels and tines off. I fought with the right side trying to remove it with no luck until I realized you only really need the left one off. You can get a puller on the tines if they're stuck.
Engine, handle bars, tine shield everything has to come off. Take pictures how the pulleys, linkage and springs hook up. I laid mine on the right wheel and block it up level and solid. Clean the shafts good, I sandpapered mine and put oil on them so the left side cover will slide off the shafts easily. A helper makes removing the side cover easier. Work the cover off slowly and keep the shafts pushed down so they don't come out of the other side cover.
And as they say, reassemble in reverse order.