I searched around here and could not find the answer so:

I am putting my 68 A/C car back together. All three dash panel control cables cables are cut. Is there a way to make them? Or is it just easier to buy new ones? Also where do each hook up? I found the two spots on the vent doors behind the dash but at this point it is only a guess where each goes. I would also assume the top most one goes to the right kick pannel vent? For now a/c will not be going back in. Does any one have a diagram they could scan for me? Thanks!

OK, I figured two of them out: the adjustments from floor to vent to defrost. Where does the cable hook up to control the heat level? Is this the hot water shut off under the hood? Or is it somewhere on the box under the dash.

Also I need the part that connects on the rear (cabin) side of the a/s assembley that takes the air and deflects it to the vents. It is square at at the bottom then it becomes long and oval where it connects to the vent plenum.

'68 doesn't have a hot water valve under the hood, the heat is controlled by a blend door in the heater box. It's difficult to describe the heater cable routing, PM me with your email address & I'll send you a scan from the assembly manual that should help.
BillL