Tapping Noise From Bottom End Of T110

hi
Have a Triton. T110 bottom end with a T120 barrel and top end. Bottom end is a 1962. I
Have started developing a tapping sound from the bottom end. Sounds just like tappet sound Appears loudest from timing side. Had cover off. All gears ok. Oil pump slider ok. Auto advance working ok.
No crank rumbling.
Strange thing is it get louder as engine warms up!!
Problem is getting worse. Had stethoscope on the job and picking up tapping noise from around bottom of barrels.
Any ideas as full engine strip down in the cards.

 

Hi
Decided to do a full strip down of the engine and review parts and replace. Already identified significant wear on exhaust cam followers and cam lobes. Will need replacing so going to do inlet ones as well. Going to replace crank bearings as matter of course. Hopefully crank and con rods ok once I get them out. Barrel needs replacing as some old damage to one bore. At maximum rebore so no wiggle room left. So new pistons etc.
Head needs some work as one of the exhausts sleeves loose. Few other parts identified as just about ok so given full rebuild will replace. Have a budget of £1000 so hopefully should just about cover it. At least the engine will see me out then.
Only thing which worries me is the number of triumph tools I keep reading I should have. I have learnt from bitter experience the correct tool makes life a lot easier.

 

Given I am spending the money I am then theses parts to be changed will be a given along side a few other parts which I didn’t mention.
The oil pump actually looks fine, but will change part of it. The crankcase is spotless, but that might have a bearing on the fact I change the oil yearly and only do less than 1000 miles. I think the wear I am seeing is the natural occurrence of something man made this old.