Ok, this is what I see:
The chassis is a L184
The head is CLS1840 1000W
The power supply is for the CLS2000 2000W.
The fan is rigged up to suck.
So, maybe you are correct, in that you have a CLS1840 modified to 2000W with the second fan being external.
However, I'd be very scared to plug a CLS1840 head in to an EST2000N!
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