When the patio concrete was poured it was blocked off around one side of the crawl-space entrance. The crawl-space is a thorn in my side. None of the guys seem to mind, but I do, so I am going to fix it. Part of the fixing involves a new door. For this I need to make a new frame and for it to be sturdy while not narrowing the entrance, it will extend out beyond the current one.
I do appreciate your "Here's the thing . . .", seriously if we could just know that aspect of any issue we would be a whole lot better prepared for what is to follow.
I measured the edge I am concerned with and it is two and one half inches. I don't know the depth of the rest of the slab, though it does appear about four inches on the opposite side, we are on a slope, so it seems some of the leveling was done with concrete.
It will probably be of benefit for me to check-out Handy Andy. We may be doing more with cement in the future. Mr gut is building a retaining wall in the spare time he doesn't have and so far he is planning to use bricks. I would prefer cement, for the cost, the aesthetics and for the creativity it allows.
As I have stated I am small and large power tools are not the best idea for me, unless they are stationary. I did etch off the part I want to remove with the hydrochloric acid, but the small stones are the concern for which I need a cutting tool. This is where I run the risk of cracks if I try to break it and as you say, I just don't want to do that.
I have only had a bit of trouble with the eye-rolling at Home Depot and Dunn Lumber, it is actually more of a "leave this to us men little lady" sort of attitude. I have never had a problem here on DU, chauvinism seems most often a RW problem.