Had an aquisition in my old patch that did loads of this, tbf they often spotted a 20mm hole in the boards and tucked it down there, every older system had loads of internal doors and mats usually on the 3rd step and near the lounge windows. Looked after loads of 20-25 year old (then) systems.
No shame in it PJ it will come to most of us, age can be a cruel mistress and as a man in his 40's I still may not make it to the golden years you are encountering.
I also hear these may be of use to you?