Perhaps you could borrow one of those infra-red thermometers & take some measurements. The infra red thermometers don't read shiny surfaces accurately, keep that in mind when comparing readings.
Or, weld a bung into the exhaust just downstream of the collector & give it a try.
I've never really measured, but the collectors on Panteras look a bit shorter than normal anyway.
Just the ramblings of an enebriate.
Your friend on the DTBB, George
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