This is the easiest way to remove rusted screws/bolts from tank other than paying the money to a plumber. Still will be a challenge but doable with Patience's and the right tools. Good luck on your DYI. here is a tip I did not mention in video: USE PLUMBERS PUTTY UNDER RUBBER WASHER WITH SCREW/BOLTS TO TANK !! help with leaks!!
here is the links for DREMEL 100: https://www.amazon.com/Dremel-100-N-S...
LINK for extra reinforced cutting disks: https://www.amazon.com/Dremel-426-Fib...