Does the torch plug that comes with it have the removable tip like pictured here. Try to unscrew it without damaging it. If it does have a removable terminal nut then you can use more options. Didn't know it needed to be solid but you can select solid in the website.
The electrode spec can change a bit since heat dissipation changes but it's not a problem. Heat range can be a notch higher or lower in these lower compression engines without it mattering even going up or down two won't really matter either. In modern car engines it matters far more especially if turbocharged or with an aggressive timing map but in regular car engines going up or down 1 heat range notch virtually never causes issues. It's better to go one down than one up though.
For the most part if the plug is a tad hotter you nick the timing back a tad but most put a hotter plug in with or without and nothing happens and generators run for longer so a touch colder plug wouldn't be bad since it'll take longer to get hot but in generator use it'll stay hot enough to burn deposits. What heat range do those pulstars have? They will likely work fine.
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