CMP ergo Ford Waterpumps

[Bob Moseley (RIP)]

Hi all
A common problem with restoring the CMP and military related Ford flatheads is with the waterpumps. Single pulley, double pulley etc. I was always under the belief that the single pulley pumps rotated on a bush with the doulble pulley ones on a bearing. Heard today that with the CMPs they all had double pullies but rotated on a bush. Here in OZ there were so many problems with the bushes burning out that Ford imported double pulley pumps with bearings from the UK, hence all the imported CMPs were converted to this type.
Urban myth, true, what do you think/know.
Bob