Bridgeport Series 1 cnc servo conversion

I am planning to replace the stepper motors on my Bridgeport Series
1 cnc with SEM Servo motors which are rated at 19 lb/in. I have a
couple of questions:
Are these motors suitable to use the current 1:1 belt drive which
the steppers use?
What drive ratio do the later Series 1 Interacts equipped with
servos use?

Any help/comments would be appreciated

Regards

Paul Harrington