I'd offer some help but I'm in my last week of uni so very busy indeed. If it was next weekend I could help out.

What it sounds like is that you don't have your PCV return in place, meaning the crank case ventilation and rocker cover ventilation are venting to atmosphere or simply capped with a filter or catch can.

If you were to install the stock components of the A12 of the car's era I think you'd end up with just a PCV return cycle system as the anti-pollution gear of that time.

Is there an option to plumb the return with the current weber carburetor? Or are they wanting to see the stock setup back on it?

What is the current setup and do you have pictures? If I were you I'd just plumb everything so that the crankcase and rocker fumes cycle back through the induction so the harmful fumes are cycled back through for a burn and emitted as slightly more friendly fumes. That is all the stock setup was, in terms of anti-pollution. If you have the stock inlet manifold then that should have a pcv valve on it, you just run a pipe from the rocker cover vent T-piece'd to a hose from the crankcase breather and then the final outlet of the t-piece is connected by a third hose to the PCV valve, this should work okay and suit their requests just fine.

If you want the quickest solution (and assuming you have nothing available) you may want to dash down to u-pull-it wreckers for some stock manifolds and gear. I had a spare A12 runner but gave that to another Adelaide member.