My apologies!! I failed to mention in my post that the rated digging depths tend to be exaggerated. One way to dig deeper is to bench down. ie Dig down an area large enough to position your machine in and finish digging from there. It's an added pain but if you really have to dig deeper than the hoe will reach, it's an option. Same applies whether using BH or excavator.
Sorry, Too little, too late.
Sorry, Too little, too late.