The crankshaft orientation can be found by looking at the fourth digit in the Model number (first 2 are cubic inch, third is the design series). If the number is 0 to 4 in that spot it is a horizontal shaft, while numbers 5-9 indicate a vertical shaft. Your model has the number 4, so it is a Horizontal.
And based on the year model if the shroud is original, it will have the shaft mounted steel skeleton rockers. They aren't good for high rpm or spring pressures.