318 head porting for the average joe

Today i decided to do 'just the guide'. I shortened it's length where it starts to about a 1/2',

pardon me for being a complete noob, but can you please explain exactly what you mean by this? Do you mean 1/2 and inch from where the guide begins? If so, what effect might that have on the life of the guide insert?
And where are the updates? I've been hanging out for me DIY tips. (My dremel and carbide burr kit should be here by the weekend)