Haven't been able to find the factory fender struts and sissy bar for mine.
Check out Ginz Choppers - here is what they told me:
Hey Dave,
You can see a customer installation on a 2002 Mastiff on our Customer Pics page (4th bike down on left side). I believe your bike has a fiberglass rear fender. The fiberglass fender is too weak to use for the bolts. Therefore, for this installation, you need the sissy bar mount bolts on the inside on the fender bolt up flush against the inside of the struts so the installation is strong and secure. To do so, you need to drill larger holes through the fender so the bolts tightens against the inside of the struts.
 
Our universal mounts come with step by step instructions and two drill templates.
 
Thanks,
 
Ginz Choppers
949-916-5926 (office)
http://www.ginzchoppers.com/