If you use just set screws with the gas block, this is very much a DIY job.
Now, if you are wanting to pin this block, using the coil pin-you're going to need a decent drill press, some cutting oil, and some sort of rig to hold everything steady.
The good news about the Geissele block is that it makes pinning a gas block easy when compared to other pinning solutions (in that they typically need a separate/special pinning fixture, having to source your own taper pins, etc). The bad news is that pinning a gas block still really needs a drill press or the like to be done right. I personally don't trust myself to do this with a hand drill.
Set screws with threadlocker, generally speaking, make it so the block won't be going anywhere. If you're going to be running around OCONUS, kicking doors, or generally relying on the rifle daily-then yes, you should pin it.
Reasonable enough?