This is probably similar to the conversion process for the Firebird cluster, but couldn't find a write-up for the Camaro (93-96/7), so here it goes..
First, you need to take the cluster apart and retrieve the curcut board from the back of the assembly.
In the where the tach connects to this board near the bottom there is a small capacitor with a black and a white IC chip on either side of it. On my board it was labled C6
It is the one I am pointing at.

De-solder this from the board.
To replace it, you will need a capacitor with the correct value.
V8 1500 pF
V6 2200 pF
I would recommend a ceramic axial capacitor with a fairly low tolerance and not above 50V, I bought mine from Digikey (V6 to V8), part # 399-4485-1-ND
Solder the new capacitor back into place, reassemble and you are good to go!
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* 97 Olds Cutlass DD
* 86 Mustang SVO Rear Ended, R.I.P (Sold)

* 86 Fiero GT, Soon to be Northstar
[This message has been edited by 17Car (edited 07-10-2011).]