I've had lots of engine building experience and this is one area where you need the special tools. Not so much for getting the guide out, but for putting the new one back in. If you want to try it yourself, heat the head in a oven (200 F). Drop the guide in the freezer for awhile. Then lightly tap it in. Use a plastic or brass hammer. If the guide has a shoulder you can tap it in with a socket over the guide, contacting the shoulder. Just don't tap it on the top with anything hard or its toast. When in doubt, get a machine shop to install. Will always need a valve job, new guide will change the line up of the valve and seat. Just my two cents.