It's very easy.
Requirements:
- The ability to match a drawing to youre NES board
(so you can identfy the correct chip)
- Its also handy to be able to count atleast to 4 (so you can clip the correct pin)
- Being able to clip a piece of metal (so that you have disconnected pin4)
- Optionally you should be able to handel a soldering iron so you can reconnect the remains of the pin4 (the chip part) to youre ground.
Just kidding with the list, its really easy to do. just make sure you look good at the drawing wich says wich chip to cut pin 4 from.
About nes/mattel I have no idea, could it be that matterl is some NOAC? or is it just the same size as the NES itself?
Goodluck with the region-mod.
-- edit --
Was just reading some wiki paga and found the following:
European "Mattel" and "NES" Versions. In the UK, Italy and Australia, two versions of the NES were released, the "Mattel Version" and "NES Version".[26] When the NES was first released in those countries, it was distributed by Mattel and Nintendo decided to use a lockout chip specific to those countries, different from the chip used in other European countries. When Nintendo took over European distribution in 1990, they produced consoles that were then labelled "NES Version". The differences between the two are the text on the front flap, a smoother finish on the top of the "NES Version" console and being compatible with US and Canadian NES systems.
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