yeah its done as a 1.8 upgrade, bolt the 2.0 bottom end and the fecker flies in comparison!
the setup will make better power than the 20seh as long as everything is in good nick
you will need the full inlet & injection setup as well as the head, the valves are a bit larger, but its the huge ports that make the biggest difference
theres a few pics of it on my 8v site http://8vastra.web1000.com
that was my concern aswell, i only want to do it, if there is a noticeable improvement. think ill stick to the original plan and wait for a cheap second hand b+ head as i know they are worth 10-15 bhp and roughly same increase in torque