I was job-hunting in my late 50s (looking at anything from supermarket shelf-stacking upwards) until I reached 60 (when I qualified for a small pension from my teaching days):
Over 2000 applications.
Fewer than 200 replies.
Only 3 interviews.
After one interview I was provisionally offered the job but, a few days later, the 'big boss' decided to reorganise the firm and the job no longer existed.
After another I did a 13-hour unpaid shift as 'work experience' and never heard from them again.
After the last one I did one day's unpaid work experience and then another paid day, during which time I did all the required work and also, at their request, sorted out the firm's health & safety policy statement, which the boss had been struggling with for months. I was then denied the job on the grounds that I was 'too intelligent'!
Good luck, Dave! I think that you'll need it!