I have not, but use to day ski into Gabro lake and beyond. Usually, the road was plowed only up to the Kawishiwi river entry point, but it was easy traveling to the Gabro entry point due to snowmobile activity up to the entry point. Also in the past dog sleds used the Gabbro portage and then went thru the grass swamp south of little Gabro to reach Gabbro. There could be logging activity that might extend the plowed part.
Very easy to find out-call the USFS-Kawishiwi station.
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