LS16Blade has done a good summary of what happened in 1981-2 above, though I will add one point: we spent money like no one else in the Division. Keith Waugh, Colin Morris and King Keith all cost about 100 grand.
Let's have a look at 1988-9.
Looking at people who played regularly, what is striking is there was continuity at the back, and almost everything up front was completely new.
After a turbulent season for goalkeepers, Graham Benstead came in on loan at the end of the relegation season, and played the majority of the season until Simon Tracey usurped him towards the end. he was a big improvement on Andy Leaning.
The defence was very similar to what we had seen the previous season (and the one before that, for that matter). Stancliffe, Pike, Wilder and Brian Smith were all regulars. A few players Bassett brought in during his whirlwind transfer activity the year before (Darren Carr, Cliff Powell) played only the odd game. This defence did quite well at a lower level. Hence there was not much rebuilding at the back. Steve Thompson came in later on when Smith had his horrible leg break.
Cental midfield, where Bassett liked a two, was also initially based on players we'd had the year before. With Martin Kuhl gone, Mark Todd and Simon Webster were a pair for a few months, but this did not last. Webster also had a nasty leg break, and Bassett brought Bob Booker in to replace him. That did not go well initially, but after Mansfield away something clicked. John Gannon came in on loan with about two thirds of the season gone, and over this season and the next gradually usurped Todd. Martin Dickinson and Wally Downes might also have seen action here had they not both had bad injuries. So here things evolved over the season.
It was up front and out wide that Bassett rang the changes and did his best work. There were two survivors: Peter Duffield, who had never convinced, and Tony Agana, who had looked good but was not fully fit. To this mix Bassett added in pre-season Ian Bryson from the SPL, veteran Francis Joseph, old fashioned winger Alan Roberts, and some gangly kid that United had seen when they'd been watching Dave Cusack at Doncaster, Brian Deane.
Joseph and Deano scored at Reading on the opening day but Joseph got injured. Agana started the next league game, so we had a front 4 - and it was a front 4 - of Bryson, Agana, Deane and Roberts. We beat Bristol Rovers 4-1, and away we went. 93 goals, with 24 for Agana, 22 for Deano, and double figures for Bryson and Duffield, who tended to switch in and out with Roberts. No Blades player had scored 10 league goals for 3 seasons. This was a feast after a famine.
The rebuilt forward line was not only crucial to this promotion but to going up the following year two, where Bassett did the opposite: he completely rebuilt the defence and only tinkered with the forwards. It was masterful work.
The problem this summer? Major surgery is needed all over the pitch, a bit like 2016. Perhaps someone else can summarise what Wilder did then!