My PA8010 Powerline light does not illuminate when connected to the router and plugged in to the mains circuit.  This fail is recent and may have been connect to a local line fault.  Having tried numerous factory resets without success, I am inclined to get a replacement.  The choices seem to be a TL WPA 8631 pasthrough kit, or a PA9020 passthrough kit.  The models on the TP site suggest that both kits do the same thing, but the 9020 consists of two extenders (from the photos) whereas the WPA consists of an adapter and an extender.  Is this a correct assessment and woykld the WPA 8631 work with my existing extenders?