It would be a fun project to do for the "hell of it". But there is no need. You can buy eBay BOVs, that will likely work better than your homegrown one will, for very cheap.
I have a friend that made one, we still joke about it. He ended up buying one.
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC