The two parts you refer to are really easy to remove, once you understand how they are installed. They are located in the thin space between the wall of the tank and the sheetmetal housing. They are held in place by spring tension, with the weak spring pushing them tight. You may have to tap them with a screwdriver if they are corroded and stuck, and maybe bend a tab back on the tin, but they will come out.
Step one on any trouble shooting with these things is clean electrical connections, and many problems are resolved once they are cleaned. I typically sand all the male posts on the stake on connections with an emery board. I then use a pliers to lightly tighten the female end, it necessary, and shot a little WD-40 in them. They should actually leave a light scrape mark on the clean terminal after they are installed and removed. The control board can also be dirty enough to cause issue. If you pull the multipin connector off, you can clean the contacts on the board, with a pencil eraser.
