There you go ... two days of talking and a genuine offer from a buyer

What value do you put on it Sid?
Two genuine offers Sir.
I would have thought it was all in the frame/chassis number. That's the ONLY thing that counts... surely and is what makes it what it is, unique.
Without that, its just a bike in tarts clothing.
I must agree and disagree, the value of this bike is in it's pedigree, it is what it was, it is a piece of history and member of racing royalty any way you cut it. Any nob can build a replica, I am a nob and I am building a matched set of early PD's with PD tanks painted like the Marlboro bikes. I watched the races as a kid and pieced the bikes together over years as a labor of love and when they are done I will put them on a trailer and take them to San Diego and disappear into the Baja for a month.
This bike however is different, just as a climber who has done Everest is different than some anorak with a new pair of plastic boots and a weekend hiking the Gouter on Mont Blanc. It does not matter if all that is left is the frame and engine and as nice as it would be to have the original bodywork, in racing, machines are repainted and have the plastics changed many times in a career, frankly it is a shock that this beauty still has the original block. No, it has not been kept in a time capsule with Gaston Rahier’s sweat still moistening the seat, rolling on flattened tyres checked by the Senegalese sun and covered in dust, but as far as I am concerned that makes it even more interesting and valuable.
As for being a bike in tarts clothing, even a stock R80GS with a high capacity tank painted zebra stripe is more than a bike, it is, in the opinion of many, the finest touring bike ever built and if we will remember this is the very reason that it was chosen and so successful in the PD races. The fact that it has a large capacity tank, small fairing and hand guards hardly detracts from the bike, it is dressed as it should be!
I have been a tech on German cars for 30 years and had bikes for 15 of those years, I lived on the Baja for 8 years where I had an adventure travel company and have driven every inch of it on two and four wheels. I was based in London for 6 years and did documentary and film work all over Africa and Asia and the Arctic.
Through all that I learned what works and what does not and the R80GS works, it can be rebuilt in a 2m x 2m mud hut in Mozambique with a few more tools than fit under the seat, it can be welded, tweaked and repaired with the most basic tools found in any moderate village and it shares parts with enough other bikes built over a long enough period of time that you will never find yourself waiting for parts from Austria. You have no limited service life paralever so you don’t need to strap that spare to your back, it can go down in the rocks without cracking the trans in half and if it does go down, and it will, you pull the bars straight-ish and climb back on rather than wondering where you can find an obscure magnesium casting to hold the throttle on the bike in Angkor, Cambodia. If anyone can show me a more reliable, tougher, easier to maintain and repair motorcycle with production numbers as high (considering the interchangeability of BMW parts), then I will buy it!
I envy you Sir, good luck, and sell your moms dentures before you part with that bike. If a man has his health, a box of tools, that bike and a Motorsailer there is nowhere on earth he could not get to or go.