Outer Limits 4x4 Board

I have a mate who has a 60 series diesel , he is looking at getting rid of it , can anyone tell me how much the over drive is worth,

If you can sell it off the truck as a testdrive b4 you buy, its probably worth $500 to someone with a 4 speed...but you really need to find someone looking for such an animal....they are rare but the 5 speeds are getting easier to find...
Andrew

Questions:

Would it fit a 40 series with the handbrake on the drive shaft?

Does it reduce the strength of the driveline?

How hard would it be to install?

What % overdrive does it give?

I have a mate with a V8 40 series that doesn't need to be revving up at 2500rpm on the highway. He looked at the 5 speed option but it was way too expensive due to the chassis crossmember being in the way, or having to move the handbrake.

The main motivation would be fuel economy so I guess its not worth spending huge dollars to save a couple of bucks every highway trip but if we can get confirmation that it will all work, I could have a buyer.

The 40's came out with a 5 speed later in life....the fairey has a higher overdrive ratio than the 5 speed (.78 compared to.85 for the 5th gear...yes you can run the handbrake on them....parts for the fairey are non existant but if it is in good nick, it would be alot easier than a 5 speed conversion as all shafts stay as is.

ebay auction 150063339045