Here's a video showing the BEST EVER way of hiding levers and buttons. https://www.youtube.com/watch?v=8jDgtvMxoa4 I did not invent this, nor is this my video, but I did discover this independently and it is very useful.
Try using a redstone torch key. The Youtuber Mumbo Jumbo has a video of it on his channel.
EDIT: Found it. https://www.youtube....h?v=zhg67kberPw
Don't use any that involve BUDs or BUD Switches, they were removed, and this video is a bit outdated.