[Poppy's Carrier]

Seasons greetings my name is matt and i have recently aquired a bren gun carrier hull, which i intend to restore. I am currntly trying to decipher the hull number which appears to start with a ''S''there is a definate number on one of the front tow hooks and it is 283A, i have spoken to some people in regards to this number but it draws a blank?. I was hoping someone on the forum may be able to shed some light . I will try and post some photos soon. Cheers matt baker.