Ended up adding some plumbers Teflon tape on the threaded end of the fitting. I hand tightened to start until I couldn't tighten it anymore. Then I wrapped a towel on it, took out a long tool to add leverage, and it spun around nice and smoothly. All is well now. Just to reiterate, hand tightening alone doesn't seem to be enough.
Took Sledge out for a good hard run (no rev limiter hitting mind you), with 600 miles(1000km) on the clock, boy do I feel good having installed both the Elite can and the Chevrolet Performance supplied Oil Separator kit
Just wanted to note, upon sticking a Q-tip inside the original hose to install the oil separator kit("clean side") I observed one to two at most, clean looking drops of oil in there. Nothing significant at all, but considering that I haven't even hit the track yet, something worth considering.
As for the "dirty side" where the catch can goes, although the oil looked clean inside the nipple leading to the engine, and the hose itself that needed to be removed, there was a significant amount of oil in there. By that I mean, estimate perhaps 10-20 drops of clear looking oil.
Highly recommended mods no doubt about it!