Glad to see you posting about the cat! Beautiful machine and it's clear that you've put a very healthy dose of 'owner luv' into it and when that happens then there's all those little things that can't be seen online that have been done.
As I mentioned, I posted it on here because it's worth what you're asking even in a down economy so I actually hate to see you sell it now but at least it's winter and prime cat selling season.
I've had experiences where folks hang onto the owner's manual and then they sell them after the cat sale. So, all those 'throw-ins' are worth something. If it does sell and if it is shipped through a vendor then I would HIGHLY recommend locking all the parts in a metal box... and I mean really locked. I've had truckers jimmy locks, etc... and pretend it was the wind and I lost good parts in a few cases. Hopefully your buyer would show up in person so it's a non-issue.
Here's a photo of a 'New Old Stock' 6-series sprocket and also various sprocket styles on the 4T/6-series ...so you can compare how worn your spares are vs. brand new so you can gauge how 'used' they are ...in some instances the 'worn' ones are practically new but with the standard scruff marks of grouser contact.
Best of luck with the auction! This should be an interesting one... the commercial places definitely have the coin to sink into it and look to flip it but with shipping, etc... how much more would they get? Probably not enough to warrant the purchase... except for those who also have personal collections.
which would qualify as a 'good home'. Otherwise it will be a private buyer that simply has wanted a 6 for a while and if they know what's good for them they'd buy this thing for the reserve/more. I've found there are lurkers out there on the forum with deep pockets and it could get snapped up on the auction...who knows. Almost worth a betting pool!
These machines only appreciate and particularly so when work is done proper and you've documented progress like this.
Good luck!