Standard, Code-Built Openings
A door built for a house from Manor's era is almost always a steel sectional on a standard 7-foot or 8-foot opening, with a factory-installed torsion spring system sized to a code-built jamb - not the older side-mount or extension-spring setups you'll find in neighborhoods from the 80s and 90s. That's the good news for a DIY attempt: less mystery hardware to work around.