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Would it be possible to create a category page for the product type, and represent the models with expandable divs? If you have to maintain separate pages for models with unique feature sets (separate SKUs) one tactic you could employ is to rel=canonical the individual product pages to the main category page. Other questions: are the images unique: is the alt tag unique for each image, and filename?  Is there a distinctive SKU or model name which can be part of the canonical? I had a similar situation with an audio product manufacturer. Some speakers were sold as pairs, some as individual units, some where identical product information except for color. Our solution was a a change towards category pages, since for the most part that was better for retail partners discussing our products in general, and it was easier to handle the issues involved with product end-of-life.

No, you can't actually tell or suggest to Google directly which sitelinks it should use. You can tell it which site links not to use, and hope that it chooses another instead. In Google Webmaster Tools under Site Configuration > Sitelinks there is an option to "demote" specific sitelinks that you don't think should appear. Sometimes Google replaces it with another sitelink, sometimes Google just removes it, and sometimes Google decides to ignore your request. But for getting new ones on there, the best you can do is make sure that the most important pages are linked to from your site's global navigation, and make sure there aren't too many not-most-important pages in the global navigation to confuse Google.

For link management, I recommend with no restraint Raven Tool's Link Manager. The kind of raw data they provide on all of your prospects are outstanding. If there's ever a chance in anchor text or location of the link, you're immediately notified. I don't know much about Wordtracker's Link Builder, but I can tell you that the link builders I trust me use Raven Tools and absolutely love it.

Yes, linkvalue from Website A will transfer to Website B. This will work best if Website A and Website B are about the same topic.  If they are not about the same topic then this might not be a good idea. Also, before you do this you should ask.... 1) do both of these sites have the same linksources? If they do then those duplicated links might not be worth much.... also, 2) will the webmasters who linked to Website A be pleased to see that they are now linking to Website B.  If not, you will probably lose some of your links. Good luck!