Here's thought on bearings for the larger type turbines. Have 2 tapered bearings back to back set with about a 0.001" end float then about 5-6" down the shaft put a spherical bearing. This arrangement is widely used in gearbox's and would lend itself to RE on larger machines.
Please note these are just my thoughts and I'm not trying to tell you how to mount bearings as I know you guys have been doing it for years.
Cheers Bryan1