Andy, if you can keep your w108 do it. In a few years they will have all mostly disappeared given their relative low value as a collector. As a result, the few remaining may go up in price, especially the ones in superb condition like yours (I saw the fintails going up lately) . If you need to sell it now, why not trying the UK market? It's a RHD car and UK w108s must be quite rusted out by now. You may fetch more money for yours there.
I owned a 6.3 some years ago. I was lucky to get a relatively low mileage car with a interior in mint condition. But I still spent a lot of time and money bringing it back to high original factory standards. It is indeed an amazing car but there is a lot that can go wrong on it and parts prices are in another league. To the point that I decided to sell it when I considered it was at the top. This may seem strange to some as bringing a car back to high factory standards is the final objective of many enthusiasts. But I like to enjoy my cars and I drive them a lot. I was not enjoying the 6.3 anymore because it had reached the point where it deserved to be preserved rather than worn. So I had it sold by Kienle in Germany. I was very pleased with their service, I could not have fetched the same money they did if I had advertised it on my own. Andy, you may consider contacting them to sell your w108. Its condition may have them interested in it and they have clients all over the world. So a mint RHD example may have all its chances.
It is my 6.3 experience that brought me into the M117 conversions in my W111 coupe and in the Pagoda. The 6.3 is a factory hot rod, and I wanted to keep enjoying a similar driving experience into cars I like the shape better. I wanted them reliable and simpler on a technical point of view, and I indeed enjoy them a lot without that preservation vs wear dilemma I ended up having with the 6.3.
