Removed the 2 bolts holding the gear head to shaft. On my model I had to remove the complete trimmer head, then using 2 wrench take the trimmer head adapter off the gear heD. One video showed simply putting a screwdriver in the notch behind trimmer head and unscrewing complete head. Mine of course was slightly more involved but still quite easy once I saw what needed to be done.
Remove carb cover, remove 2 t25 torx head screws. ( they are loctite in so they may be difficult). flip up carb, install new carb. swap gas fill and return lines to carb. choke and start, go to work.