My 16x7 - 4" BS Cragar Soft 8's
wouldn't even clear the stock 16" 4runner calipers without wheel spacers. You may be able to get by with the $6 .25" "slip-on" spacers that
wheelers sells to clear the 199s (scroll to the bottom of the page). But, that's going to be really iffy.
If those cheapo spacers don't work, the next smallest spacer size you can use with the Cragars to clear the Tundra brakes without replacing your stock wheel studs is 1". Many people on here run the 1.25" Spidertax spacers. I have 1" hub/lug centric spacers made by
Motorsport Technology and I highly recommend them.
The Cragars will definitely not clear the 199 or 231mm Tundra calipers on their own!! Also, consider the fact that you will feel a power difference with steel wheels. Going from stock alloys to steelies is about the same power loss as going up a tire size (like 32s to 33s). I recommend checking out the 16x8 - 4" BS ProComp 8069s - they will clear the 231s without spacers and they're alloys so they weigh a lot less than the Cragars (but look almost identical). Believe me, alloys do make a noticeable power difference.
Check out this thread if you haven't seen it already..
http://www.toyota-4runner.org/3rd-g...ements-231mm-13wl-tundra-calipers-rotors.html
It will answer all your install and parts questions for the TBU and at the bottom of post #3, it lists some other aftermarket wheels that are known to clear the Tundra brakes.
Can't answer question #2, never seen them.