There's lots of pictures out there on folks that have done this.  Go through the "List your setup" thread and you'll see lots and lots of ways to do this.

• Leave out the motor bearers, put in doublers and a strong firewall, mount to the firewall
• Keep fuselage strength all the way to the spinner ring, mount to the spinner ring
• Hog out the bearers for motor clearance, mount the motor to aluminum angle.  Using one just doesn't look strong enough to me: most people that do this must agree because they use them fore and aft, with a bearing mounted on the plate on the bell side of the motor.  Get everything mocked up and aligned, then glue that bearings outer race to its angle with epoxy.

Square corners put a tremendous load on the motor bearings because of gyroscopic effect, so there's quite a few mounting schemes that feature an extra bearing outboard of the bell, to support the shaft.  Bob Hunt mentioned this in his CL Stunt column a couple of years ago: his motor was eating bearings until he added the support to the front of the motor (which was rear mounted).  On the other hand, folks here have reported no problems with just mounting the motor on one end: I think that the high-end motor manufacturers have wised up to the needs of the 3-D RC folks (who put some pretty severe gyroscopic stress on their bearings, too), and have beefed up their motors.

Last fall's (or maybe this winter's) issue of Stunt News showed Tom Morris's method, which is a refined "hog out and make brackets" approach.

Leo,
Contact Tom Morris, he has some excellent mounts for front mounting on profiles. He also has the setup for adding a rear external bearing also.

Best,        DennisT