been searching but cant find what I'm looking for. Have GC1 and doing a restore. My slate has stains and really thin bondo from the last guy that installed it all over the slate. My slate are pinned to each other and he had used bondo or what looks like bondo. Its been 14 yrs and when I removed the felt it is coming off and gritty feeling. He also mounted my slate on backwards to the legs so I am redoing that as well, but repainting also so removing the slate anyways. I have to scrape off the old bondo as it doesnt look like beeswax. Is it alright to use a wire wheel brush to lightly clean the slate? it just doesnt feel smooth at all anywhere on the surface. I can get a brass bristle wire wheel brush also.