and, the method most accessible to a small American patrol to disable the aforementioned tank?
P.I.A.T, Bazooka or Panzerfaust (captured) fired at UNDER 100 yards into the tracks/bogie's is a possibility open to your "Small American Patrol", failing that call up the "Taxi Rank" of Typhoons armed with cannon and rocket. In a truly mobile situation I doubt that your "small American patrol" would tackle something as large as a Panzer, they would have used the "shoot and scoot" policy to get away from the danger and then call in air or artillery support to finish of the monster! - armour vs armour the only thing capable of taking on a late model panzer would have been a Sherman "firefly" (a Sherman up gunned with the British 17pdr A/T piece rather than its standard 75mm piece).
I suggest that you read this wiki article:http://en.wikipedia.org/wiki/M4_Sherman
snip:The original Shermans were able to defeat the relatively small German tanks such as the Panzer III and IV they faced when first deployed in North Africa. Later, they found themselves more evenly matched against the newer up-gunned and up-armored Pz.Kpfw. IV medium tanks. Shermans were often outmatched by the 45 ton Panther tank and wholly inadequate against the 56 ton Tiger I and later 72 ton Tiger II heavy tanks, suffering high casualties against their heavier armor and more powerful 88 mm L/56 and L/71 cannons. Mobility, mechanical reliability and sheer numbers, supported by growing superiority in supporting fighter-bombers and artillery, helped offset these disadvantages strategically. The relative ease of production allowed huge numbers of the Sherman to be produced. This allowed many divisions, even many infantry divisions, their own organic Sherman assets. Some infantry divisions had more tanks than German panzer divisions did. This was a huge advantage for the Americans.