Kat.....
Maybe you already have a multimeter, IDK. If not, I still suggest a $25.00 multimeter over a dedicated ohm thingy for 510 connectors. But that's me.
I'm sure Catt or I can solder up a 510 connector tester setup if you want one...all you'd have to do is clip the probe's alligator clips to the wires. So get alligator clips for the probes too.
You don't NEED a special connector though...you can just use the probes. Sometimes it's awkward to hold though.
This way, you can also test battery voltages off the charger. And they are more accurate for ohms.
What do you think Catt?