Where is the drain tube and heaterhoses located?

What is the exact problem here? That you need to detach drain tube and heater hoses-

Disconnect negative battery cable. Drain cooling system. Raise and support vehicle. Remove drain tube. Disconnect heater hoses from heater core. Lower vehicle.
Remove left and right sound insulators from below instrument panel. Remove steering column opening filler. On Skylark, remove console (if equipped). On all models, remove floor outlet duct. Remove heater core cover and heater core. See Fig. 10. To install, reverse removal procedure. Fill cooling system.

Dunno where the AC drain tube, the heater core hoses are attached to the 2-tubes-see no2 heater core on the pic

Isthe core leaking coolant. If so it will be leaking from the ac drain on the r/side outer a/c case at the firewall. Thats where you will have to remove the clamps and hoses. Then put large bolts or old spark plugs in the hoses and recure the clamps until u replace the core. Make sure u use a clamp u tighten with screw driver.

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