Anthony Powell can rebuild it for you:
http://www.dodgecoronet.com/forum/showthread.php?p=77246#post77246
"Below is a canned letter that I send to everyone showing my service and what 
the charges are. So far I have been able to get the switches back in the mail 
the day after I receive them. If your car is and air car be sure to check your 
temp selector switch located on the right side o the plenum (picture #3). The 
average cost to rebuild the switch is usually about 45.00 plus 5.00 for 
shipping. It just depends on how much work needs to be done. If your buttons 
are a little hard to push it usually needs at least 2 of the wafer boards. If 
your really lucky you can get off with just the vacuum port repair.
I would need you to send me your switch or switches. There is some machine 
work that I have to do no the switch. I can fix several problems that happen to 
most of these switches. The cost just depends on what is broken on your switch. 
I can fix AC/Heat or Heat only switches. I have rebuilt switches for people all 
over the United States. Rick Eburg did an article on my repairs in the March 
2006 edition of Mopar Action. 
Picture #1 is a before and after shot of the vacuum control 
It will work on any push button mopar switch from 1959 to 1988.
Picture #2 is a before and after shot of the push button repair Picture 
#3 is a before and after shot of the Temperature selector switch for 62-65 b body air conditioned car
Picture #4 is a before and after shot of the max cool vacuum switch that piggy 
backs on the fan switch on the 62-65 B body air car
Picture #5 is a before and after shot of the sliding wafer boards that go inside 
the switch.
I have been using a repaired switch in my car for over two years now and it 
works great. The port and button repair is made out of black or white delrin 
material. It is super tough. The other two switches are made of alum. They 
will all outlast the cars they are going in. The wafer boards are made out of a 
super tough plastic shim stock. The vacuum port repair is 35.00, button repair 
5.00 each,and wafer boards are 5.00 each. The temp selector switch is 40.00 as 
is the piggy back max cool switch. Just send a money order for the services 
that you think you need. I won't know if you have any bad boards in the switch 
until I open it up. If there are bad boards you can send payment for them when 
you get your switch back. I can be reached at 
aepowell3@verizon.net or 
(903)-893-5674. I thank you very much for this chance to show my product. 
P.S. Please send switches only. No metal parts.Anthony Powell1305 North Grant Dr.Sherman, Tx.75092Here is a link to some pictures of my 65 Coronethttp://www.PictureTrail.com/gid5749122Here is the link to the pictures of the switches<a href="http://www.picturetrail.com/gallery/...14&uid=2774278" target="_blank"><img src="http://pic16.picturetrail.com/VOL651...-202933225.jpg" border="0" alt="Free Image Hosting at www.picturetrail.com" /></a>
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