Unfortunately no ... one day enough engineers are going to leave EFI to start field upgrading all the useful bodies out there with newer hardware. It is POSSIBLE, but no you can't really do it without being an engineer lol.
The QS2 Pro is basically a 6 color GS2000Lx Pro. Same heads, except the GS2000Lx Pro is 8 color and LED.
In a perfect world you'd be able to change the QS2 lamps over to LED, add the nitrogen system, change software over to the GS version, and you'd be ready to roll. Unfortunately, there are some electrical differences between the two presses that means I couldn't say if it would explode. For 1, the GS presses are all 8 color, no 6 color. So i'm not totally sure if the new Vutek manager will support it. It might though ... as the head board should only report back the heads that are installed and on which channel. Or you could just "cheat" those channels off, or add all the necessary plumbing for 8 color and Fast4. Second, the GS presses use a completely different transformer and powerbox/breaker. I believe some of those aspects are controlled by the front end, or at least error codes would be all screwed up. Third and last ... as a power user, but not an engineer, I'm guessing there might be a few little sensor upgrades or motor changes that I don't know about and would be an issue.
The frustrating part is that the QS2 uses all of the same main components of the LED brothers ... same heads, boards, backplane, etc. Really they should just release an LED upgrade kit with software for that press. Unfortunately, the QS2 was released in-between the QS2000/QS3200 series and the GS2000 LED series - so they weren't out for long and there are not many of them in the field. So not much demand for upgrades. Besides, EFI isn't in the business of doing what's best for their customers ... why upgrade us for $80k when they can force us to buy a new machine for $300k?
Hoping some EFI engineer jumps on to tell me I'm wrong because I have a QS2 Pro