Is it safe to take that whole unit off? I'd like to just do that, put a block off plate on it, and then just put a cap on that vacuum line fitting.

Also, if thats capped off, it idles better, but wont rev out. Uncapped it idles REALLY rough, and revs out. I've only revved it a couple of times since putting this motor in (which was previously boosted). Its also got Stage 3 Crowers in it as well.