Paragraph quoted direct from THE VH4D Repair Manual from Wisconsin Motors not some wanna be Wisconsin site!
" FIRING ORDER"
"The firing order of the cylinders is 1-3-4-2, and the magneto and battery type distributor rotate at one-half engine speed, as is the case with conventional "inline" engines. The intervals between the firing of the cylinders is 180 degrees. No. 1 cylinder is the one nearest to the flywheel in the left bank of cylinders, when viewed from the flywheel end of the engine. No. 3 cylinder is the other cylinder in this bank. No. 2 cylinder is the one nearest to the flywheel in the right bank of cylinders and No. 4 is the other cylinder in this bank. The cylinders are numbered from 1 to 4 on the air shroud near the spark plugs. The flywheel end of the engine is designated the front and the power take-off end, the rear of engine."
Contact them at Wisconsin Motors for your copy of a VH4D repair manual and parts manual. They emailed me one last year no charge. It's factory literature not stuff rewrote by others online or mixed up stuff in wanna be repair manuals. Lots of confused manuals out there.