I used to pickup a 6ft flail mower with a power lift on a 47 A. I am not sure what it weighed but they are not light and it didn't have a problem lifting it. You do have to watch as it drops fast when you let it down. They were designed for cultivators and you wanted a fast drop after turning at the end row. It is either up or down. I don't believe you have the control you have with the Power-Trol.
If you can find a Power-Trol it isn't too bad a job changing it out. I have had mine on JD 50 off changing a seal in the lift cylinder. You do have to take off the rear end plate so you do need a motor lift.