That Brava engine is from the Lampredi SOHC family (Fiat 128-Strada-Uno etc.). You would be better getting a 1.8 or 2 litre TC engine and gearbox from the Punto/Brava/Stilo, which will give you a fighting chance of using the Beta rear (diff) mounting to start you off. You will have to fabricate the other mounts to suit the tilt-forward reverse port engine.
If you want a fairly good 1.6 Beta engine and gearbox I have the power unit out of my 1.6 HPE. I took the head off but it's all there if you want it. It's just cluttering my garage at the moment! It was a good runner before I removed it for my V6 project.
Cheers R