Good luck Kev I hope you make it.
I could tell a similar tale from an ATC gliding course in 1956 to determined to finish the PPL now on a pension.
Point of interest, don't know your club policy but do you have the "PPL Confuser" for the exams? Well worth £20. My brain is also wore out at 67 but I got 96% on Air law, I'm not bragging, because I couldn't do it again without re-reading it all.