I wouldn't buy a timing light just yet. Most likely dealing with high resistance in the starting circuit, whether it be cables, connections or the starter itself. Sounds like you are on the right track.
The crane unit is indeed an externally mounted electronic ignition. I believe they use the stock rotor.
ONE TIME TANDEM AXLE PACKAGE DEAL
ONE PACKAGE AVAILABLE AT THIS PRICE
5 14X5.5 T06 WHEELS W/GUNMETAL INLAY
5 ST215/75R14 KENDA LOADSTAR KR03 RADIALS
STAINLESS CENTER CAPS, LIFETIME CHROME LUGS
MOUNTED, BALANCED & READY TO INSTALL
SNOWMOBILE TRAILER TIRES & WHEELS
PM or email me for package pricing.
CARBURETOR REBUILDING - $125 + PARTS
LED lights, Chrome & Powder Coated Lugs