Wow Jason - is there really no saving it if you're not getting any money for it? Surely an exhaust manifold (used) can't be impossible to find! Of course, that all takes time and money.
A German buyer, who was looking for the cheap to insure in Germany classic V8's, helped me find
all the rust on the car. That was one of the contributing factors to convince me it isn't worth the time and money rescuing the beast
again. I'd rather buy a mint condition W116 in the future than spend thousands restoring mine. Even though the car is rather special to me.
Oh and the Becker radio if your car has it is definitely worth something - don't forget that and the amp box underneath the glove box.
Unfortunately my car does not have the lovely Becker radio. Instead it has this odd Vector Research stereo:

It works OK and I have the manual for it. I'm guessing it's a dealer option in the States?
The amp box? Sounds doable but I hope it's easy to spot.
The grille ahead of the windscreen can be removed by taking the wipers off then sliding it forward (Oscar mentions this here Link)
Hinge up the small cover on the wiper arm pivot and remove nut, hinge up wiper arm and remove (might need a bit of force). Pull off black plastic cone piece, remove nut. Grille is held by four expanding plastic rivets, with a pointy tool, push the locking pin in the middle of the rivets right through and out of the rivet. The grille should now be free.
koan
Thanks. This grill will be one of the important pieces to tie the W116 theme living room together!
Things like the instrument cluster, glove box door, interior trim are worthwhile things to keep.
Instrument cluster I may or may not leave. Here it is:

Glove box door, sure thing. It has a crack in it though:

The only way to remove the woodwork properly is to remove the dash top, but it is probably worth the effort, as it is reasonably sought after.
How is removing the dash top done?
I understand the dash is hard to get out, but depending on the colour, if it has no cracks I would pay you enough to make removal worth your while.
Unfortunately the dash has a big crack near the instrument cluster. It looks far more obvious looking at it with your own eyes than the pictures lead you to believe:

Thanks for the advice so far guys. I'll be sure to take many photos when stripping day begins.
Jason