The heat sink is not riveted on, but appears to be glued on. I have not
really tried to remove it yet; to test the parts I removed all 6 of them
(the heatsink is a single one across all 6 parts).
Perhaps the FETs could be wired back into different locations for test purposes
using extension leads without having to detach them from the heatsink?
Regards,
Peter Coghlan.