I worked at a tire shop for several years and we used buffers, you might look into that option.ha ha ha well I'm glad to be back too. Yeah after 1hr's worth of work today and only about a 2"x4" piece cut out, I'm gonna look for a cheap groover. Thanks Rob!
See good thing I started on the geckos.
One thing for sure, the cleared area is much softer now that the material is removed.