6-8psi isn't a great deal and won't be dramatically increasing charge temps but a cooler is definately a good idea..
I was running around 10 psi with no cooler and and it would only detonate on hot, dry days but the power difference between hot and cold, dense air temps was massive..
It's always better to be safe than sorry and even though these are tough as nails motors it's good to have some assurance.
A small side mount like the guys have said would be plenty for what you have and could possibly want and is cheap so do it.
get some pics up!!