Hello there,
you don't have to remove rear bumper to replace rear reflector/s, I believe the reflector will prise off gently with a small flat ended screw driver, the new one should simply clip back on.
The reflector has at least one holding clip that's moulded to it, plus will have a
guide lip/tongue to aid fitment.
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From 2008 to early 2010 part number 6L6 945 105A (for standard & FR models)
Cupra model is 6L5 945 105A
Left side rear bumber reflectors.
From 2008 to early 2010 part number 6L6 945 106A (for standard & FR models)
Cupra model is 6L5 945 106A
Right side rear bumber reflector.
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6J3 = 3 door model
6J4 = 5 door model
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From mid 2010 to 2012 part numbers
6J3 945 105B & 6J3 945 105C
Left side rear bumber reflector.
From mid 2010 to 2012 part numbers
6J3 945 106B & 6J3 945 106C
Right side rear bumber reflector.
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From mid 2010 onwards up to 2017 new part number added for 4 door models 6J4 945 105A & 6J4 945 105B &
6J4 945 105C (left side rear bumper reflector)
Part number 6J4 945 106A &
6J4 945 106B & 6J4 945 106C
(right side rear bumper reflector)
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From mid 2012 to 2014 part number
6J3 945 105E
Left side rear bumber reflector.
From mid 2012 to 2014 part number
6J3 945 106E
Right side rear bumber reflector.
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From 2014 part number
6J3 945 105G
Left side rear bumber reflector.
From 2014 part number
6J3 945 106G
Right side rear bumber reflector.
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Hope this helps
Si