You can also find much information on your air rifle in the Archer Airguns blog at http://www.archerairguns.info
Click on the link that says QB78 Family under the Blog Topics heading on the right side of the site. There's 67 posts for you to enjoy there
Also, you will find YouTube videos for how to install the XP Tune Kit and undertake other work on your air rifle in the Archer Airguns Channel at http://www.youtube.com/archerairguns
As you can see, many thousands of others have found these videos useful.
I hope you find this information helpful. Have fun with your TF79!
Archer Airguns Inc.
Online stores http://www.archerairguns.com