I have found two different inverter boards in the 27” 2011 iMacs. One, like shown here, has a 4 pin connector on the top edge that a small connector with 2 wires coming directly from the LCD panel plugs into. The other has an 8 pin connector with a cable about 16” long that goes from that connector to the 8 pin connector on the logic board labeled BLC_ACDC. I’ve come across this configuration 2 or 3 times, out of 40+ iMacs I’ve refurbished.
The inverter board with 8 pins has a part number of V267-E02HF and they sometimes show up on eBay. The cable has a part number of 593-1435 and they’re impossible to find.