Wait wait wait. This isn't going to work. Is it? You still cannot get more that 2000W from the pair.
1000 by itself is 1000
2000 by itself is 2000
2000 + 1000 is still 2000.
The smaller gen will go into overload, while the 2000 will be at half load.
I haven't done this before, but this is how running parallel power supplies works. A 10A and a 20A parallel will only give you 20A, not 30.