Hello- I live in central Ohio and just picked up an all original 74 DT 360 that doesn’t run. No spark and I found the pickup coil is ‘open’. And apparently getting a pulser/pickup coil is impossible. So, I JUST ordered a 12v conversion from Rex’s Speed Shop. Anyone have experience with this?

Welcome from NZ.
Hope you get it up & running soon.
Others on here have experience of Rex's & other brands so i'm sure will be along soon.
Re-the pulser just to be sure you're testing it right, my book on SC500 with the same basic full flywheel mag says white/red to white/green 85 ohms [so around that value] but looks like nothing to earth & only between.
Go my 360A running 30 years ago--ride to work bike--which had the start retard half of the pulser faulty so either earthed half the pulser or earthed the cdi box color relating to retard, likely green/white.
Too long ago but started on advance so had to kick it hard or she kicked back like a mule.
Just thinking--ya must get a reading to earth if you earthed one of the colors then touched the other with the meter & probe to earth.
Or is that just doing the same as testing between the two in a roundabout way.
Sorry--woffling & remeniscing of the good times. But wait--there's more lol.
I have one motor running with no pulser--DT360a mag on an older motor--pulser was smashed off on a mag i bought, so just used the source coil only & a Suzy coil box combined, just a single wire from source to coil/box combined, common RG50 LT50 JR50 you name it.
Worked good surprisingly. Don't take too much notice of me lol.

Pulsera was definitely bad. It had been hit and slightly smashed at some point. The bike hadn’t ran for 12 years. I put a little oil on the plug hole and slowly cycled the kick start, then let it sit for a week or 2 waiting on my 12v stator from Rex’s, cleaned some light rust from the tank and cleaned the carb good. Got the upgrade  installed and she fired 5th kick and held a good idle. Didn’t take it for a ride yet because I have no brakes and the front forks have no oil. Now, just waiting on more parts…

Greetings from Tennessee  

Top Man, great news.