Fixed car, kinda. More questions

A clanking noise isn't pinging. Pinging is more of a tapping or rattling, like marbles in a tin can. I don't kow what the clanking could be.

I see you have BBK headers, are you still running EGR equipment? EGR flows exhaust gases back into the intake and into the combustion chambers to help cool them (exhaust is 600* as opposed to combustion chamber's 2000*). This way at part throttle, the computer can kick in a TON of timing to increase fuel efficiency. If the EGR is taken off, and the computer is not told about it (the ONLY real way to do this is to go into the PCM with a chip/tweecer/pms) then it thinks there is cool gas flowing through there and so it adds the timing, when really the combustion temperatures are a lot hotter than they should be. Extra timing (on top of that base 10*) and hot combustion temperatures will lead to pinging.

Sooo...................... do you still have EGR?

You can disassemble the actual valve, and there will be a plunger that moves in and out. You can secure this plunger half in and half out, that should at least keep the CEL from coming on. There's really nothing you can do until you get the tune, just take it easy.