If I do the air dog II and the GDP big line kit do i need the h and s fuel plug and shim kit.

 

No.. I would not plug regardless of application sans comp drags/Pulls.

By plugging, your eliminating the rails relief valve.. Or in other words, your asking for trouble someday when you get up on it and blow your injectors apart.

The plug is a race-only application. You can shim it to raise the relief pressure but I highly recommend against a plug.