Thanks! DCR oil modifier is easy to install for me atleast. I've done several installs. When I install them I make sure I install them properly. Some people do it in 30 min but I'm more cautious and ensure it gets done right so it takes me a little bit longer. What I do is everything that needs to be done with something else that should be done. If your careful you can save the gasket and o-rings. When you take the valve cover and gasket/o-rings off. The top of the head where the gasket/o-rings sat on has dirt, sand, dirty oil, residue and so fourth. I use the scraper/razor/box cutter to scrap all that off and ensure a clean top of the head for the gasket/o-rings to lay on. That's the extra step I take. A bit time consuming but it ensures a tight/clean seal and you also don't have to worry about boost leaks or any oil leaks.
The one on the car... Quoted from there website. "Increased compressor inlet size, ported compressor discharge, port and reshape turbine housing to include DCR exclusive "ramp" mod." Other options can be found here: http://www.dcrsrt.com/index.php?act=viewProd&productId=66