[Matt Monson]

Core: $2500-3000
Bearing Plate: $275
1/2 shift sleeve: $275
3/4 shift sleeve: $295
synchros : $115x5 $575
Labor: $1000

That puts you at $4920-5420. That does not include any bearings (up to $1200 in parts) or a 5/r slider ($800). No dog teeth ($125 ea) and another $100 for a gasket kit and new nuts for the ones that can't be reused. One can easily spend $5k making a core into a good gearbox if you buy a "good used" core here. I say start at $5k and be negotiable.

Mag case 8:31s ran from 1975 through 1977 in a variety of models and I have even seen some 915/61 mag gearboxes in early productions '78 SCs. Is it mechanical speedo or electronic? The mechanical speedo is pretty rare and only 1975. I would add $500 if it's mechanical because that 8:31 was a one year only item.