I'm figuring it'd be easier or quicker to just throw a bigger engine in. There's a reasonable amount of room under the bonnet and the firewall seems to have a cut out for the 3S-FE head so that's why I liked the idea of being able to bolt in the 3S-GE. Assuming that's possible with the standard five speed and mounts etc.
As for what I do with the 7K I'll wait and see if it's a happening thing first