Besides airflow you may want to cut the case too because a lot of the times it will cause an annoying whine because of the grates on the back of the case.
Most here do exhaust even though you may get a few degrees cooler doing intake it isn't worth heating every other component in your case getting those few degrees for your CPU.
The H50 TIM is one of the best if not thee best TIM but, it has one downfall they put way too much on it. My suggestion has always been to put a rubber glove on and take it all off split it in half then reapply that should give you about the right amount.
Good luck with your install