While looking for some examples of the work of the recently deceased BBC journalist John Cole, I stumbled upon this rather extraordinary video of the BBC's 1992 election coverage.
I only made it about five minutes in, but up to that point you have some pretty interesting viewing, from the overly dramatic TV graphics--which seem more 'X-Factor' than 'Serious Politics'--to the broad and diverse selection of posh accents and the effort to invest the results in Basildon with some sense of drama.
My favourite line: David Dimbleby's ringing announcement (at 1:45) that, 'Here in the studio, we've got bank after bank after bank...of computers.'
That was still the kind of thing you mentioned in 1992, apparently. (And I wonder whether your average smart phone today might be able to handle the number crunching that required those 'banks' back then.)
In any case: the BBC's exit polling in 1992 clearly left a lot to be desired.