I would certainly speculate same weight as it will be one combined class with 1.9's and 1.6's under the same rules (per my understanding).
Denny

I would not expect a concession on weight of Gen2's vs. Gen3's after 2018 at the National level. At least they aren't going to throw the Gen2's out like they did with the Renault's after '06 (sending many of us on the West Coast to NASA for at least a season and many on the rest to the sidelines.)

Don't see why there's any reason why there couldn't be a Regional-only class that allows the Gen2's to be scored and trophied separately in non-Majors events, though I don't expect a different run group would be possible. For a while we opened up an extra region-only "SR" class to allow entry into multiple races on a weekend (though coordinating group 3/6 to allow this was a bit of a challenge and I think the group 3's folks were not that excited to have SR in a group of xSR cars.) ASR was bandied about a bit as another potential "catch-all" slot though technically the SRF does not meet GCR requirement for other classes due to the roll-bar construction.

Heck, SM has at least three groups out here (SM / SMT / SSM) plus a myriad of IT "alphabet soup" classes so we don't have a challenge out here inventing a class if it will get drivers to race more.