Daniels Defense sells a quadrail that free floats but doesn't need a different barrel nut. It goes back to the receiver over the delta ring.
Saw one last week. They make nice stuff.
The dude wanted a full length handguard, over a dissipator bbl (has shaved gas block at CAR position, dummy one up front).
The DD quadrail would not go over the shaved gas block. It needed a bit more shaving.
If you have a midlength bbl, then a DD midlength quad of that type (if they make it, bet they do) should work fine.
You'll still need to remove your front handguard cap from your gas block, if so equipped (gas block/sight GI style) as it'll rattle against the front of the free float quad rail.
No biggie, somebody around should have the benchblock for quick pin knock out. Neat little item to have