The 67c has three condensers - the bottom-most two (the big ones labeled "A" - where the convex sides face each other, the bottom pointing up and the top pointing down) are always left in the enlarger.

The top-most condenser was used for 35mm negs only. My 67c manual has an addendum stating that the newer version - which uses the 75 watt frosted PH140 edison-base (standard household socket) screw-in bulb vs. the older bayonet style bulb - doesn't need the top condenser for 35mm negs, and that they stopped including it with the enlarger, but left the slot for it vs. re-tooling the condenser box casting.

So... if that' the one you're missing, you may be good.