Actually, I don't have the part numbers. The Allison 540 4sp tranny that I am replacing already had the brake on it and so I just had the Allison distributor move it over to the Allison 1000 when it was being converted from having a transfer case for 4 wheel drive to being a two wheel drive setup. The tail shaft housing must have the provision for the brake. Allison can give you the number for that tailshaft housing.
As a side note, the website that hosts my photos is having some problems as a result of foreign spammers and is no longer available without registering and no longer has the pictures from Dec 2013 to now. When that gets sorted out I will update the pictures and provide a fresh link.
Progress does continue as I am in the process of positioning the engine and tranny so that the motor mount brackets can be welded into place.