the crossmember will bolt straight on to the au, what do i do with the wiring and ECU can this be wired up properly...
also does anyone think it is also possible to get a Boss 290 converted to GAS cause i don't like the price of petrol these days..
will i get the same power as i would using petrol...

I've heard of them running Gas, not sure about the power difference, I think it would depend on the gas system, a liquid injection system would be the best, and possibly no power lose, maybe even an increase.
ECU and wiring will be the hardest part, I believe that the BA/BF need the original dash, stereo, BCM and ECU together for everything to work, Do some research and see if that security part of the ECU can be disabled with a flash tune. Then the best would be to transfer the whole BA loom and ECU over.

There is a guy on fordforums.com.au that has swapped one into an XY, maybe have a look as what he has done ECU wise..

Good luck.

Shouldnt be too tough to get it working on an aftermarket ECU.

am i right in thinking u have to modify the shocker tower...

AU and BA engine bays are much the same. Ford insert the engine through the bottom of the car.

The Modular engines are on par with Big Blocks size wise.

FTG Autosalvage and a few other places have got these to run with the factory computer (no ICC or any of the other rubish)

what gearbox do you run or plan to run with this?