I believe you'll have issues mounting the 6BT to the chipper. What engine was in it before? If it was other than a Cummins, you'll have to change the motor mounts and reconfigure them. I don't believe I've ever seen a 6BT on a Woodchuck. If it had a Cummins, it would more than likely have a 4BT in the chipper. You could also have an issue with the clutch if you go with the 6BT. Most chippers that are a 4 cylinder have a single 11" disk for the clutch. Most 6 cylinders have a double 11" disk. Another issue could be the size of the dog house as it was designed for a 4 cylinder and not a 6.
I would consider finding the make and size of engine that was in the chipper previously.
I wish I would have had more positives than negatives.
Hope this helps!
Dave
Global Equipment Exporters
770-420-6400