Thanks to all. I just found my answer on a BimmerForm site. It says:
You can undo the four (4) nuts at the driveshaft/differential flange, but there is insufficient movement to slide the driveshaft forward enough to get the studs clear of the flange.
There is the possibility of loosening the gland-nut at the center (driveshaft support) bearing, and perhaps the spline can be compressed enough for the studs to clear the differential flange.
The short answer is no to the dolly, and yes to the small tilt-bed trailer.
Other comments about oiling, method of oiling and gear selection (constant mesh) are all correct.
So in a nut shell no can to no way no how. Trailer only