I don't think you would have a bit of problem with the reach. Come to think of it, I think even a very small backhoe would probably do it.
As far as depth, better let the experts say for sure, but from my reading as I recall 3-5' depth. I can tell you about equipment and operating it, but when it comes to fish most of what I "know" has come from reading and little practical experience. Just the last couple years have I gained much hands on.
One other thing I recall from reading here on PBF. Wish I could remember who posted it, but maybe they will recognize the story and take recognition. Someone had "washed" quite a lot of lime into their pond off of a barge of some sort. Well all ag lime has a few solids that are larger than the fine lime. So when he was done with the job these coarse lime (which was actually very fine limestone gravel) dropped directly to the bottom of the shallow area where he was washing the lime into the water. So there was a pile of it on the bottom. As I recall the story, the poster said the BG loved this gravel and spread it all out into beds. So it started out as a pile and the fish rearranged it to suit them - ie spread it out.
Point is, I think all you have to worry about is getting the gravel to the desired depth and making sure it does not slide on down the bank. The fish will level it out. I think as you uncurl the backhoe bucket (while putting pressure against the bank) it will push up enough mud ridge (with the back side of the bucket teeth) to keep the gravel in a shallow pocket. At least that is the way it is woring in my "minds eye". Sometimes my "minds eye" needs glasses though and it does not work out like I planned
. So if you decide to try doing it this way, verify it is working to suit you before going on to "bed #2".
