Jerry, I'm not sure on converting to degrees, I'm sure someone can help with that, but I use the depth measurement on a cheap digital caliper down the bore hole.
$20 or so will get a cheap digital 6" at Menards, TSC, etc., and you'll find it handy a lot more places. Just make sure it has the "tail" coming out of the end, that's what you use for depth measurement, and I've seen a couple real cheap ones that don't have one.
thanks steve. wouldn't you know it. i just bought a dial indicator 2 months ago at HF with no tail piece. BTW you may know the saw i'm talkin bout.