I made a homemade copy of the Bald Eagle floating reamer holder, but with a minor change. Instead of having the reamer holder have an internal rear flat surface which bears against the rounded pusher in the tailstock, I instead pressed a ball bearing into the rear of the holder, and that bears against a flat pusher. My reasoning being that if the pusher is rounded (as in the Bald Eagle design), it will bear pressure off centre on the reamer holder, if the reamer holder floats off centre. If its the opposite way around as I made it, then the reamer holder will always have pressure centred on the reamer, even if it is deviating from the centre of the pusher as it floats to follow the bore. Plus, it was easier to push a hardened ball bearing into a hole, than machine a hole with a perfect internal flat surface for the pusher to bear against.