" Out of about 6 or 7 sand buggies I've looked at, only 1 has had the lower cooling baffles installed. These are the little shrouds that are attached (clipped) under the cylinders, they direct the cooling air properly. I'm under the impression that these things are critcal to efficient cooling."
There are actually two 'baffles', the smaller one is on the bottom of the cylinder head and is pressed in and held in place by four metal 'fingers'. I use a small flathead screwdriver to push them into the head casting and they seem to stay put.
The other one as you noted is between the cylinders, and yes they are important. In fact if you take a look at Tom Wilson's "How to rebuild your volkswagen air-cooled engine" book on page 133, he writes "Just as soon as you get the cylinders on the engine install the lower air baffles. These are the sheet-metal pieces that snap into the cylinder head studs, covering the space between the cylinders". He then goes on to state in bold print that if you forget to install them you --must-- backtrack far enough to get them in there, and not doing so is a 'big mistake'.
Perhaps this is why the dune buggies are for sale. Mysterious chronic overheating, so the owner decides to sell and move on with life?
Believe it or not, I once saw a bug for sale with "runs great" on the windsheild. The engine had -no cylinder tin- at all. It had a fanshroud and nothing else. It blew me away that someone would assemble an engine like that. Little wonder the thing was for sale.
Chris