It is possible, as long as the software and CPU are at the correct revision levels. I can't remember for sure (it's been many years since I did an upgrade). I believe the CPU must be a 432-11 (maybe -10 would work) and sofware 6601-632. If your machine is not up to the minimum level for drip feed then an upgrade CPU and sofware is needed. This can be very expensive, if you can even find what is needed.