turn the drive all the way to either left or right, then you can remove the 4 screws. to totally remove both trim limit and trim sender, you need to at least pull the drive. as i understand, to replace, they come as a pair(kit) now.
Curb your enthusiasm . You will have to pull your drive, and remove the bell housing hinge pins and pull the housing back so you can access the 7/16' cap screw on the clamp that holds the wire's sealing grommet. You'll want a ratcheting 7/16 box end wrench with a pivoting head to access the cap screw. You'll also need strong small hands.
my contacts on my trim switch, not the sender were gooped up when i got boat and would intermitenttly work until i cleaned them. i also had worn, exposed copper at the base. i used permatex liquid electrical tape to seal for now.