Hi there,
That is interesting you say that on the side dump. To me it looks just like the AD side dump offered in the Perf. Options catalouge. On the original cars they ran some other options from AD as I see such as GTA campy wheels on the front.
Agree on the ports, as we all know this is where the real power is made. I am still curious as to the cams they used and if they bumped up the compression as they did with the ETCC entered cars. I have a feeling they also used a different exhaust manifold, maybe a GTA manifold and as VInce says most likely 45 Webers. I assume the stock 2L 4.56 gears were also used, not sure. I am sure that little items from the AD catalouge were used.
Doubt they used a sliding block on the rear of these cars, probably just a stock 2L suspension with differen't springs, Koni's and adjustable control arms. As Vince says you can notice the rear arches have been pulled allowing for bigger rear wheels.
Everything else I am just speculating. I am so intriged, to know the accurate details though