Ticking/tapping sound from engine on acceleration

This might sound weird, but I used to have that problem on a '67 when my oil was low. Simple, but true. I've also seen that when you rev the engine, sometimes the fans are too close to the radiator and when the frame moves, the fan starts hitting it. Just a thought.

sound like a lifter or tappet problem

you might also want to replace the exhaust manifold gasket, the escaping gasses can give a tappet like noise under load

I would check the exhaust gasket as well as check rocker arm torque....the procedure should be available online, the easiest messiest way is to idle the engine with the valve cover off and tighten each rocker arm slowly untilyou hear the engine bog down, then back off half a turn. be extremely careful doing it this way as oil has a tendency to get everywhere and if your exhaust manifolds get to warm you can have a fire.

sticking lifter,change oil & filter.run a pint of trans fluid in old oil,let it idel,dont reve motor,it will clean out engine,drain back holes in heads,let it idel for 15 minutes drain oil ,oil filter put in new oil,oil filter.it will stop clicking.

Other thing is the gas... it took me a while to remember to put in as high of octane gas as I could find. Using regular unleaded will make this sound too.

If the ticking is on acceleration its likely spark knock, Check your timing

My 82' blazer ticks when I accelerate