Removing the EGR is no problem

The std ECU could be re-mapped but if your planning no mods besides what you have said there is no need

Don't make the exhaust too large in diameter if your gong to use the std ECU they just don't like it and don't forget to make sure you have the Lambda bosses in the system as you will need the O2 sensors for the std ECU.

Not sure about the belt

Using the granada rad is ok but the A/C fan might not be good enough to keep it cool but fitting an electric fan is a good idea.

Hope that helps