How hard is it to replace the temp gauge and the clock in a 69? How much has to be taken apart to gain access?

It is not difficult at all. Disconnect the battery.

Remove the passenger side lower dash. Then you will need to remove the center gauge bezel. Removal of the driver's side lower dash allows easier access to disconnect all of the connections behind the cluster.

The back of the gauge bezel is clearly marked to make reconnection easy. You may have to wait until you start to remove the bezel to gain access to a couple of connections. When you disconnect the oil line take precautions to keep oil from dripping in the car. When you go to reconnect the oil line use a new compression fitting. U do not want a leak!

To get out the center cluster and bezel you will need to get off two nuts that hold the bezel to the console. Then remove the screws that attach the bezel to the driver's side dash and dash pad. Make sure you have all the screws out of the bezel. Very carefully pull from the top of where the gauges are to get the whole assembly out. Do not pull on top of the bezel because it will break!!!! If there is resistance you may need to heat up some of the vinyl around the bezel to soften it up.

Once all is disconnected the bezel should lift right out.

It should become pretty clear that the entire cluster has to be removed to get the oil gauge out. The clock will come out from behind.

Make special note of where all the little gaskets and stuff go when you start to take the cluster off the back of the bezel.

While you are at it now is a good time to replace all the bulbs since it is apart.

Hope that helps. It is no big deal with patience.

Good Luck!