Value of old S&S B

[Fenton Murray]

Dear list,
I'm looking at an old 6'10" Steinway s/n 68xxx, 85 note with intact ivory, 
original finish was ebony now ugly antique white with all original case 
parts in reasonable condition. Piano is basically a rebuildable shell 
needing a board along with everything else but it is playable and usable as 
is.
In trying to advise my client I would like to give them some idea as to it's 
as is value and potental completely restored value.
Help, please,
Fenton