Excuse my ignorance but I'm having trouble understanding what you've said. Would you please clarify the the following:
Spark arrestor installed to carb - What does that mean?
Heater box internal baffle is trimmed for clearance for the spark arrestor - Where's the heater box? Are you referring to the plastic cowling around the carb?
When they did the recall on my B & S engine, they said they just replaced the primer components.
The rework kit involves adding a spark arrestor to the carb. There's not enough room in there for the spark arrestor they've used so there is some trimming of an internal baffle in the heater box.
Yeah, a heater box is the plastic (metal on Tecumseh) shroud around the intake.
If they just replaced the primer components then they are negligent and you may still have a hazardous unit. You should call and clarify what they did or pop open the heater box to look for the spark arrestor screen.
PK