Transall/PN, thank you.
An unthinking question on my part: I knew it was the C2 that was replaced by the MB seat - only to stupidly think that the C2 was the downward firing one. And I know, if I think about it, that the C2 was a zero-zero seat...
A downward firing zero-zero seat? Doh!.
(is there a smilie for 'shakes head at early onset of dementia?)