Does the Vendee have a vertical rear triangle like the others in the Soplair range Bob, or is it something like the one on Hob's Puck?
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If it like the others and looking at the photo you've added, I don't think you'll be able to get it to fit. There is a certain amount of flexibility in the rear section and it can be "leaned" by a small amount but because you have a Puck the Omnistor is far too close. That's only my opinion however.
On the other hand, if the awning you are looking at has the sloping rear section as per Hob's photo, then you're in with a chance, I think? Hob is the man to ask.
Randa