Like the Stock variant? Hmmm... good marketing shot, doesn't show that all the guns can't point forward!
Or like this using Predator Turrets on top http://weemen.blogspot.com/2010/08/land-raider-terminus-invictus.html like Pornstarjedi did.
Or like this extending the side sponsons out http://www.flickr.com/photos/jmcgreen/5797543449/in/photostream/
Or this triple side sponson http://www.bolterandchainsword.com/index.php?showtopic=120879
Or using this on top... http://www.forgeworld.co.uk/Warhammer-40000/LASCANNON-RAZORBACK-CONVERSION-KIT.html
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