The BH92 hoe on my L6060HST has a separate seat. The tractor seat does swivel but only a few degrees. It doesn't come close to facing rearward. When digging long trenches, I bent up a piece of pipe which hooks onto the HST treadle. I use it to move the tractor forward as I dig. Steering is a bit of a chore and requires reaching over the tractor seat to grab the wheel. Not pretty but it saves a lot of time climbing on and off the tractor.
Unfortunately, I'm trading the L6060HST for a L6060HSTC cab model and my scheme will no longer work. I plan to mount the BH92 on my MX5800 and use it for excavating instead.