I did the job on both my Mini-14 and 30, it was a pain in the ass, but they both came out nice. If I had seen that 1'' sling before, I think I would used it first, but heres the job I did:
I removed the rubber butt-pad (just two screws) and I drilled out the hole that held the rear sling swivel, using a rat-tail file I fit a A2 sling swivel from a AR-15 butt-stock.
I then I drilled out the back of the mini ranch stock and use a lower bolt from an M-14 butt-stock to hold the rear AR-15 sling swivel in place, replacing the lower wood screw that was on the Ruger stock.
The front sling swivel I removed the "Loop" from a German 98K swivel mount, after I re-sized the hole in the gas block on the mini (don't drill to deep) it fit right in.
Drilling the gas block on the mini was very hard, the rifle is stainless steel.
Heres the M30:
and the Mini-14: