Howdy all. We really like the look of 1-inch (nominal) glass mosaic tiles. We have purchased several "sheets" (12 x 12 inch nominal) and will be putting them on the kitchen walls. I have purchased white thinset (premixed), and plan to use an unsanded white grout to finish. I have a few questions: 1. The current wall material is drywall, with a 1/8" concrete coating with a top-coat sand texture and paint. The wall surface is extremely durable, and in perfect condition. Is there any prep, other than de-greasing the painted surface, to get proper adhesion of the thinset? 2. We'll be doing tile 9" up from the counter (which is a backsplash-free oak butcherblock), and then all the way up to the ceiling behind the range hood. Any tips to keep all the lines looking parallel and perpendicular? I don't suppose chalk lines would work once the thinset is up. That's about it. I'm pretty sure we can do this, but I thought I'd ask for any pointers from this DIY group beforehand. Thanks!