https://www.theguardian.com/media/mind-your-language/2014/nov/18/mind-your-language-another-think
The Guardian says the OED quotes an example misusing 'thing' from Only Fools and Horses (series 1 episode 6 'The Russians'): “If you think I’m staying in a lead-lined Nissen hut with you and Grandad and a chemical bloody khazi you’ve got another thing coming.” However, David Jason as Del Boy employs a subtle yet definite glottal stop and says ‘think coming’ not ‘thing coming’. Scripts online also have 'think coming.' Perhaps the OED's source misinterpreted it, as ‘thing’ can have a ‘k’ or glottal stop as in ‘sumfink’. But even if that is Del Boy’s habit too, it is too much of a stretch to claim the word here is thing not think.
Why does this matter? Well, what if one day the OED quotes 'should of' wrongly and designates it correct English?
Kudos to @soupyspoon for the original thread and @SequinsandSoleros for their post that unearthed this.