Did that once. It's not hard
There's resistor settings on both the motherboard and the processor card for determining bus speed. If either one is set to 133mhz then the bus will run at 133mhz. If you're changing the processor that would solve that problem.
To change the resistor setting on the motherboard you need to remove R676. It's located on the bottom of the motherboard right under the rear left corner of the processor socket.
In case you want to play with your currant processor. On your dual 867 card you need to remove resistor R22 to change it's bus setting from 133 to 167. It's on the top of the card to the rear of the left hand processor. If you don't do anything else your 867 will be trying to run at 1083mhz. It may or may not do that. Mine had 933mhz processors and handled it but I may just have been lucky. There's lots of info on the web on overclocking MDDs. I should point out that there's a separate set of resistors for the speed setting of each processor.
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