I know this takes series takes place in the 30s/40s and the 60s/70s portion of the modern era.
Bearing in mind that Phil Sheldon has not aged that much since the 1940s, aswell as J Jonah Jameson, then maybe this series should be set on Earth-98 and not Earth-616.
On Earth-98 the 60s and 70s comics really do take place in 60/70s. Where as Earth-616 uses the sliding compressed timescale known as 'Marvel time'. so these stories would have to take place much later because of the pre-modern era in between.