I'd definitely go back to getting spark first. Especially if you had it already. Double check that the kill switch is in the on position, or bypass it.
I would temporarily disconnect the choke. If you have spark and fuel, you should be able to get it to fire. Once you do, you can go back getting the choke working right.
I just got my 50V a month ago and it took every ounce of energy I had to get it to start by pedaling on the stand. Once I tore everything apart to install new bearings and seals, I discovered the starter clutch and drive clutch were a rusted mess. After seeing how bad it was, I was amazed I was able to get it to run before addressing.
You can also run a drill on your magneto to make troubleshooting and getting it started a lot easier. I'd stay away from an impact gun though. Use a drill, start slow, and use the decomp lever/valve. Begin with the decomp lever engaged to make it easier to turn the engine and once it feels like it wants to fire, let it go.
In my case, I needed to choke the Gurtner carb with my thumb while spinning the engine with the drill. It took cleaning and setting the float to get it idle and run decently. I did end up getting a Dellorto clone though, which has been better. (edited)