I replaced mine in 2009 without too much trouble.
The unit I used was
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LG Model LWHD1006R
10,000 BTU Cool
9.8 EER
With Remote
Unit Dimensions:
20 3/32"w, 13 7/8"h, 19 3/8"d.
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This exact unit I don't think is made any more but hopefully you can find something similar. Please post if you do because I will probably have to replace this again in the future.
Here is the thread from when I did it:
http://www.trailmanorowners.com/foru...ead.php?t=9014