Au xr6 tune

[Ford Falcon XR6]

Hi Everyone

Been quiet a few years since I've posted on these forums. I finally have some time in life to tinker around with my au falcon.
I have a stage 3 cam which I've had sitting in the shed for years I want to fit it to my Au 3 xr6.
Question is what is the quickest and easiest way to get a reliable tune.
I've read alot about quarter horse but would rather something that is just done first time. Don't really have the patience for revision after revision.
Rang a few tuners in the Sydney area no one wants to touch an au. Keep getting the same answer "too old don't do them"
Ideally would be drive in drive out dyno tune.
Don't want to go an aftermarket ecu must be easy to return to stock if desired.

Thanks Lorenz