Valve stem seals are pretty easy to replace as Benz stated you need compressed air, a fitting for the spark plug hole, a KD valve spring compressor and a few hand tools.
The job is pretty straight forward, if you'd like I can give you all the details.
Understand this YOUR GUIDES ARE GONE! seals will help w/ oil consumption but you really need a valve job, I did the same thing at 149,000. It made a huge difference in oil consumption. (1qt. per 1,000 miles to 1qt.per 3,000)But I really need the guides replaced, too much $$ right now.
Chris C. firstname.lastname@example.org