stevenson_18

Ok I have a built b20 engine that im going to boost, It had a b20 valve cover on it with two ports for a catchcan but they were jb welded and broke, So I went and got a ls valve cover. The b20 valve cover has a pcv in the top of the valve cover, where as the ls does not. My motor also does not have the black box on the back of it. So my question is if I vent the b18 ls valve cover with two vents and run it to a catch can is that right? or do I have to port the back of the block as well? Ive read so much diff stuff its got me really confused. Any input would help and thanks!