Advice on getting a parking permit for a Camper Van

Does anyone have any experience in getting a parking permit (residents or otherwise) for a vehicle falling outside of the dimensions given by the council on their website?

We are considering getting a van to convert into a camper, and one such vehicle being actively considered falls outside of the maximum size for "passenger or goods vehicles: 2.27 metres (7’6") high; 5.25 metres (17’3") long" that the council stipulates.

It may be a complete dead end to look for something falling outside of the eligibility criteria... everything else is clearly ineligible by definition!

But i wondered whether any HoLers had come up against this issue and if there are other kinds of permit or solutions that could be sought to get a permit to park on our road.

We're not talking about a motor home or anything collosal, but the option being looked at would be around a metre longer and approx half a metre taller than the sizes above.

I figure that a general enquiry to the Parking Permits office would illicit a standard response referring me to the relevant dimensions above (and maybe it deserves such a response!) but if anyone has run into this issue before and found a fix, I would be grateful to hear it.

Thanks