I am struggling with the rel="canonical". If each product had its own product PDF then it would be easy to use the rel="canonical". However, some of the PDF manuals cover somewhere between 200-300 products. The only difference between some of the products is the physical size (like televisions i.e. 32" vs 37") so the same manual covers all the products within that range. I am guessing using the same PDF manual for so many products is a duplicate content issue, but sadly they are really useful for users. Maybe I could put all the pdfs on the product category pages. That said the MOZ tools are showing that we only have 200 duplicate pages out of 250,000, which I think is good.
I agree with Mike, a summary of the PDF, FAQs and how to guides would be an advantage. I've already started adding this information for some of the more popular products but we don't have enough people to write content for every product. A smaller site would be a lot easier.
Anyone got any ideas?
@Dave - thanks mate