I have always liked the HB Viva, with its coke bottle lines introduced well before the Escort and Cortina and I am not usually a fan of heavilly modified vehicles, but in this instance, provided the chassis has been modified properly, this one looks the dog's danglies!
This looks very like the Viva that was built in Luton a few years ago. The chap that did it owned a sunroof company and he also built an FB Victor to a very similar spec but not convertible. He actually put the Victor body onto a Cavalier chassis so I would imagine the Viva has had the same treatment, he would have definately strenghthened the chassis, his work was/is first class....if it is one of his conversions of course