Apex does the Vtec add-on to their canopies for $450 I believe. I am guessing that having an independent rigger will cost you the same if not more. At that point it may just be cheaper to sell the ACE, and buy a vented canopy. You may even save some $$$.
I spoke to Nancy Filippino about it last year and this was her response:
"It’s not really practical to add the PAC valves to an Ace. We wouldn’t recommend it based on cost and you can risk doing damage to the Ace during the process."
If you do add vents to your Ace, I'd recommend using a valve more like the MDV (from the Troll) than the original PAC valve. In my opinion, the MDV system allows cleaner inflow and seals more completely.
Which is also an answer to the question about "why?" Because you want a different valve system than the one available from the manufacturer.