Do not trust the outline on the Sumo door as it is too large!
If you start by cutting a small groove where the outline has been made, this will give you a good idea of where the lock will be fitted.
Make up a cardboard template the same size as the door lock and mark through where the screws should be fitted. You can then place this up against the door and mark where the holes can be drilled. Once done, you will be able to fix the lock in place and then see how much the groove you cut out earlier needs to be enlarged.
Take it slowly and you'll get a good finish.
Good luck.
Tony B
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http://homepage.ntlworld.com/tony.breski