I'm sure alot of you know about thesebut for those who don't these kits are great for doing tumbler deletes,turbo housings,head work and port matching.They run about $50 and come in small engine kits as well.If you don't have access to a air grinder you can use a Rotozip.A Dremmel cannot be used because the kits use a 1/4" mandrel shank.I have used these kits on my motorcycle and vehicles and they are awsome! http://www.sa-motorsports.com

Don't you need certain level of skill to do this?

I saw these a while back, but I was too scared to **** up my heads...I wanted to do gasket(intake and exhaust) port matching...

You just need to take your time and don't rush it.I thought the same thing too.I have done a couple street port and polish jobs and they turned out great.This kit is also good for boring out the throttlebody.On the website they have the Instructions in the D.I.Y. part.You could just buy a P.O.S. $20 head from any car of ebay and use that to practice on.