The problem over here is that to re-shell a RS3100 you would more than likely have to use a 4cyl shell as a V6 item is also very rare, a lot of work can be done to remedy the differences between the two however it still is basically illegal ( commonly known as ringing), I know it happens all the time with older cars and I also am aware that there are a number of RS3100 that will never go back on the road unless another shell is used because the panels are just not available.
But the value of the cars has to be lower than that of a genuine car even if the genuine car has been the subject of a major rebuild using many new panels it still retains the basic structure and identity, at one time I would have said that if two cars were identical in appearance one re-shelled and the other genuine there would of been at least £2-3,000 difference probably more now.
I have no problem with cars being re-shelled as long as it is made clear when selling, I have however come accross a couple of incidents where individuals have purchased cars for quite a bit of money only to find out afterwards that all is not what it appears now this I do have a problem with, so if anyone ever calls me regarding an RS Capri for sale I will always inform them if I think there is something untoward about it.
Regards Len.
P.S. you guys are right it does appear to have sealer in the joint and the door fit is not the best, I know that this car suffered a frontal impact with a deer many years ago so possibly this could be the result.