Need to post pics of your oil return line installed, not just a link to the kit you bought.
MBHD You are going to need to add more vents to your valve cover, did you do that yet?
How much boost are you seeing, do you have a boost gauge to read?
The store bought octane booster does not add that much octane. If it says it adds 5 points, that means .5 points.
Torrco accelerator stuff really works great to supress detonation.
Xylene, is approx 117 octane & can be bought @ paint stores Home depot etc. Toluene 114 or so. If you want to try it. It is not good to breath or to get on your skin etc, be careful when handleing it if interested here is how to mix it. http://www.gnttype.org/techarea/misc/octanebooster.html