The guy I bought my 625 SMC from tried to do a convert with the stock rims to keep up with his dirt buddies on trails and fire fire roads, he tried some really weird tire combos.. He found information here on ADV which lead him to this original post from 6 years ago.
I have the setup on my 05 and it does really well even with 50/50s on it, here is a pic of mine with Dunlop 606s on it. So depending on how much money you want to put into it, it may be a good route. I love mine, but it is up for sale here on ADV due to health reasons.