I take it a drop in guard wouldn't be a true free float ....correct"Can the stud be screwed into the threaded hole under the gas block... see attached picture.."
Would advise against this, you don't want your barrel to be subject to loading from the bi-pod. Accuracy will suffer. Free floating an AR barrel is essential to having an accurate AR.
Connect the bi-pod to your hand guard. If your AR is in "service rifle" configuration purchase and install a float tube which free floats the hand guards.
I take it a drop in guard wouldn't be a true free float ....correct