Just one more…. If the content is different, could you run the two pages together, and then when you are totally happy with the new one, direct to it? Will google penalise you for not directing immediately?
I´m just really worried about the transition when he has such high google rankings.
What I´m trying to say, is can you wait to see how highly the new site ranks, before re-directing? And once you do that 301 direct, how quickly will the new site climb to the position of the old one?
The problem I also have at the moment, is that I don´t have complete control of his old domain and hosting. I simply don´t want any time to go past, where his rankings suffer.
No, it will be on a completely new domain. There isn´t much content to be honest, so it won´t be difficult to re-write it.
Do people think this a good idea? To build the re-vamp wordpress (on a different domain) launch it; see how it ranks; then 301 re-direct from the old site (which is ranking highly) on the old domain? And obviously change the links to the new site.