Can I add just a clutch pedal to auto pedals?

There's a folded sheet channel that the b brake pedal hangs from (it has the four studs for the mc iirc). On manual trans cars, there's a little angle iron brace welded across the legs of the channel.

If You put the clutch pedal in the brake pedal pivot pin and the folded bracket doesn't have that brace, the assembly will deflect and bind up.