This is a little revolutionary, in that though it uses the Field of Battle WWII rules, it's Vietnam. FoB WWII uses companies as the base element, so it's perfect for quasi operational level battles, without cluttering the battlefield with MGs and mortars (they operate within the base effectiveness).
There are of course doctrinal changes and helicopters, though the beauty of FoB is that it is eminently hackable. Infantry choppers can be released as an asset on a move card, and their roll on the same card permits anything to move to LZ/land/deploy depending on how good the roll is.
There were a lot of subtle changes here for reinforcements and deployment - and the fact that we used hexes to simplify movement and ranges - and to dictate limitations (i.e. almost everywhere is light jungle or ridgeline). Some work still to do but I think we have proven the concept.
Key to this battle is the fact that the NVA expected a ground drive rather than the use of Air-Mobility to support the Marines at Khe Sanh. There are also elements of forcing a low tech or less well supplied enemy into the open such that it can be bombarded with more 'high tech' or well supplied munitions. In effect, a little cold to compare, but we see the same thing from Afghanistan to the Ardennes offensive (depending on which theory you read) where knowledge of an enemy's willingness to expose itself can be exploited through airpower and rapid movement of ground units.
We used the 1980s classic boardgame 'Operation Pegasus' as source material, amongst other more general references. This is a fantastic game in in its own right and the first hex'n'chit game I ever played in the 80s. Box detail gives a good outline of the operation.
A modern reinterpretation of the original boardgame map - showing Khe Sanh, the surrounding high ground. Lang Vei special forces camp is to the left with LZ Stud to the far right.