Hi, good to hear that things are progressing. When I did my engine overhaul I also found that parts of a previous tensioner pad (and bits of tensioner

) were in an oil gallery. However, as the engine is inclined and the oil comes up at the highest point and then returns to the sump via the lower galleries, I found my debris in one of the return galleries....this is probably the same in your case? Anyhow, the oil feeds to the tappets are bored into the head and cannot get 'big stuff' in them. So, your tappet noise will probably not be sorted by removing the tensioner pad bits...mine certainly wasn't.
A new set would be a good idea as you have it all to bits at the moment...I wish I had done that, as I will have to 'get back in there' at some point soon, as the tappet rattle is driving me crazy, and a Porsche should not sound like that!
There are several ways to clean the top of the pistons however, always ensure you devise a way to stop crud from getting down between the piston and the cylinder wall, as some of this stuff can be pretty hard and abrasive. I used some cardboard to fit into the gap (gently), then cleaned the top of the piston with petrol on a brush to remove most of the oily carbon deposits. Harder stuff can be carefully removed using a soft implement - do not use anything that would score the piston top surface. But, I guess the more experienced engine rebuilders will have alternative ways to do this, as my method was somewhat crude - but effective...
I guess £350 sounds OK for that work, maybe others have an opinion? Always check that the machine shop understands the skimming tolerance for the Porsche head. I think it is stated in the WSM, as well as the valve guide tolerances, etc.
Keep the updates coming!
