Don't forget to ask Adrian for a stem adapter when you order the crown and tube. You need it for these stems. He will include it with the crown for a couple of bucks.
Then go over to Homage Forum and look at Kime's 6200 build log thread. He gives detailed step by step instructions with pics on how to measure and cut your stem using Athaya's stem adapter and the crown/tube set. There isn't much room for error, so his instructions will help you get it right the first time.