If you use a3:73 and 35's, you will run around 27.5 mph per 1000 rpm in high range top.4;10 and 35's equal 25mph, so you have a10% step up. This will stretch the chain in your 208, and if you are still running a dana 30 in the front it could be an issue. Who cares? blow it up then put a 60 in the front and a14 bolt GM in the rear. By the way, to work out gearing easily, multipy tyre height(loaded) by 2.94, then divide by overall gear ratio (my formula) it will get you within 2%.