I follow Wealdstone, and probably my interest in the development of the Scottish pyramid relates to the fact that the Stones were involved in the setting up of what was then the Alliance Premier, now known as the National league, back in 1979. The English Football League were quite pro pyamid, and applications were invited from clubs in the Southern League and the Northern Premier League, who had already come to an agreement that they would jointly support a single candidate to challenge Division 4 clubs seekinfg re-election, so as to avoid splitting FL members votes. This approach resulted in the election of Wimbledon (of the SL) in 1977, and Wigan Athletic (of the NPL) in 1978.
Following the establishment of the AP, it was felt in the Non-League game that FL clubs closed ranks a bit, and no further clubs were elected untill automatic promotion (one space only) was brought in for the 86-87 season. The NPL and SL were the strongest leagues in the North and South respectively and were semi-pro, whereas the Northern League and the Isthmian league covered some of the same areas, but were strictly amateur. Ambitious clubs from the NL and the IL would tend to gravitate to the NPL and SL, and clubs in difficulty would go in the opposite direction. The Isthmian League saw which way the wind was blowing and joined the pyramid in the mid-80s', today sitting alongside the NPL and the SL at levels 7-8. The Northern League lacked the vision or ambition, and are now at levels 9-10, and one of the feeders into the NPL.
Interestingly, from a senior v junior perspective, there remained extensive overlap between the SL and the IL for many seasons; in fact this has really only been fully resolved in the last few years. Nevertheless, I don't recall the SL having any issues with the IL joining at the same level, despite them being a few years late to the party. However, I think the remaining East Junior clubs would be unwise to draw any conclusions from this precedent.
