That's an interesting project. I had not seen it before but it appears to be an awful lot of work! The Sintratec will be good for some of the smaller parts but I think the SkullServoFix is just a bit too big. Could it be broken down into smaller pieces? Also, it has a lot of heavy, solid sections that could be eliminated if it could be re-modelled.

I am happy to have a go at printing the cooling duct and if it works out okay, you are welcome to have it. I will let you know how I get on and I will attempt it tomorrow.