On the one side, we see Heritage giving immigration reform -- a policy it once supported -- the same treatment it gave Romneycare and Obamacare-style health care reform, and the cap and trade model of reducing greenhouse gas pollution, once political circumstances changed. Likewise, in this study it abandoned its typical protocol of using "dynamic" analysis to model the economic effects of big policy changes. That tells you a lot about how desperate Heritage is to snuff out the bill. "Dynamic scoring" is the secret sauce supply siders use to cook up studies showing tax cuts for the rich pay for themselves -- or help pay for themselves -- by magically creating explosive economic growth. It's conservative movement doctrine. But in the case of immigration reform it simply means assuming that immigrants contribute to GDP and spend at least some of their money in the U.S., so Heritage tossed it out the window.
Then on the other side, we have much of the rest of the conservative establishment, now in the unusual position of aligning itself with the Congressional Budget Office, which they frequently attack for enabling liberal policy but are happy to associate themselves with when it suits their agenda.