Do you remember which IT jet airlines were regulars at Leeds Bradford before the runway extension ? As far as I can remember, we had Britannia from 1976 up until now (sort of), Air Europe in 1980, '82 and '83, Air Malta also sporadically from 1982, Monarch from 1982, Orion from 1983 and Dan-Air from 1984. All using the Advanced 737-200. I guess Dan-Air were in on Intasun business from 1984 as we didn't see much of Air Europe from then on.
Air Malta only had three 737s in the early 1980s, along with the back-up 720s, so they must have worked them very hard on European schedules and ITs.
After the runway extension was completed, it was something of a free-for-all. We also began to see 737-200s from overseas operators such as Spantax and Hispania, by which time Air Europe and Britannia were even less interested in Leeds Bradford!