At least with the one I'm working on you can still see it is a lexus in there unlike your rover Rod.
It happens to be a Series 5 RX7 fitted with twin TD04 turbos. We have been doing the wiring of a link G4 storm and then tuning. Its been running for two weeks now. Before it goes onto the dyno we are making some powersteer lines , brake lines and clutch lines. Its taken a couple of days to do the powersteer so far. Its about a 4 hour job to get the radiator out and back in to enable us to get at the powersteer rack. Brake lines tomorrow. Ill get some dyno sheets when its tuned.