Why scramble your own Sevcon (with original VIN) , that you may have to replace anyway with a new one (inc. programming via Renault an an excuse why they have to do so) if you have the chance to get a used pre block sevcon and UCH.
Then you can use any tuning tool.
Your aproach will produce a lot of roadkill along the way.
Tuners remorse when the switch to another car?
But if your customers know the toll , thats ok!