question about using angle grinder to cut chain rivets

I just pulled the 530 chain off my FT500 Ascot using my handy dandy cordless drill and a grinding stone. Took the heads off the rivets and push the pins out with my chain tool. By the way I sold this bike 2 years ago and it has returned to me a lost and sick puppy. This is the chain I installed over two years about and to say it and the sprockets are shot is an understatement.

 

Look at the front sprocket before cutting the chain off. If it is hooked, your need the rear brake (and chain) to lock the drive train and loosen the front sprocket nut.