Re: SEI 116 upper unit + alpha one GEN II lower unit - will it work?
Yes, they will work, if your lower is truly a Gen 2. If it's an Alpha One, you need the SEI 106 upper. 3.0s usually get 2.0 (later I think they went to 1.98) ratio drives.
Re: SEI 116 upper unit + alpha one GEN II lower unit - will it work?
Replacing an upper alone is usually foolhardy.
There is no way on earth to really remove the miniscule bits and pieces of the grenaded upper from all the bearings and seals of the lower.
The whole unit will fail again in short order.