Very sad to here this Sarge as I know the motors are a big part of your life. I have had spinal surgery twice in the past and luckily it worked for me and I would suggest having that pesky disc fettled at the first opportunity. Is that an option with any medical insurance you have or would you have to put your firstborn into slavery to pay for it?

A thought crosses my mind that if you cannot fettle the bigger stuff how about smaller things such as say generator/petrol mixer engines?

I have the Briggs and scrap em' type of thing in mind.

Find some that are in bad form, fettle them up as per the many you-tube videos and sell them for a small profit. Income and therapy all in one!

Not Exactly an Austin/Morris B-series workout I know but you still get to keep your hand in as they say.