Butcher

Hi Guys new to the forum, have had a Saiga 12 for 10 years or so. I have a Pic rail I want to install on the forearm for a tapco vertical grip. Can not find any instructional videos for the type i have anywhere. Can anyone help me out here? I can post whatever you need for pictures etc. Thanks in advance for the help! PS Tried to upload photos, would not work.