classic mountney boss

[DR Kauffman]

i've tried fitting this boss and wheel to the 'loon but to no avail, does anyone know how to fit this ? is there any parts im missing?

http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0146.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0145.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/CopyofSAM_0300.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0305.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0302.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0301.jpg
http://i982.photobucket.com/albums/ae310/drkauffman/SAM_0303.jpg