Can I make my Region 1 Sony DVP-NS57P pla...

I've seen a solution to convert a Sony DVP-NS57P to region free. I'm not sure this applies to my player. A few of the queries mentioned that their Sonys were sold as region free. Mine was not. Can I make my Region 1 DVP-NS57P play Region 2 and 4 formats ? If so, do I need an ''All for One Remote'' ? This was mentioned in the solution. It seemed like the All in One was being used to program keypad numbers to spit out sequences in DVD mode. Couldn't I just punch the sequences ?

Thanks in advance.