I am going to use that Yanmar until the chassis literally starts rusting apart, then I'm going to grab my welder and some duct tape and drive it some more!
As much as I would like to have a tractor with, say, about 35-40HP with M4WD and a FEL and a backhoe and a gear transmission (still don't really like the hydros, I like to know that I've got "lockup" in every gear), right now I just can't afford one. And to add to that, my little Yanmar has done EVERYTHING that I have asked of it, is extremely easy to work on (like an oil change took all of 10-15 minutes and used only ONE gallon of oil!), and I have yet to get the thing even remotely close to being stuck.
Tony123, I have to say as skeptical about the usefulness of the dirt scoop as I was at first, I have found it to be a very good alternative to a FEL which at the moment I just can't justify spending the money on, when all I REALLY needed the tractor for was to mow the pasture. The thing I have found though is the dirt scoop actually gets used much more than the bush hog does!
The dirt scoop is a pretty cool implement. I tried using it in reverse at one point. It was COMPLETELY useless. In 2WD the minute I would set the scoop down my tires would start to spin like they were on ice. I worried about damaging something in 4WD, after reading about how one should be cautios when using the 3pt. hitch to push.
When pulling it, it will really dig up a good bit of dirt. If the soil is very hard, or you are trying to dig through very thick grass/weeds, it can be tough to get started. When I was digging that trench for the garden, I had to get a hoe and make a notch in the ground to get the scoop started. After that it worked just fine.
I am not really sure how far down you can dig. 6" is probably pretty close. If you would want to dig down further, you would have to dig out an area so your wheels could go down further too, because like you said you are limited by how far the 3pt. hitch will drop.
I don't remember if your tractor has M4WD or not. If it is just 2WD, I would advise you to stay away from a dirt scoop unless your soil is relativly easy to scoop up. In 2WD my tires will spin if I hit something that provides the least bit of resistance.
Here are the things that do bother me a little bit about the scoop:
If you want to dig deeper in each pass, you have to make the top link short in order to tip the bucket down further. The problem is that when you have the bucket at a pretty steep angle, unless the soil is sticky it will fall right out as soon as you pick it up and start moving.
Also, positioning the scoop can be a challenge in a tight area, ex. when you are digging a trench and one wheel that you want to stay on the edge keeps slipping down into the trench, making the scoop go all sideways on you.
Other than that, I really don't have any complaints about the scoop. It works good and gets the job done and is the perfect size for my little YM1401D.