Big Daddy Lextreme.......... What's up big poppa?
LS models are Cathode Technology, rather than the led's used in all the other Lexi models. They are a completely different critter. The problem most prevalent with the clusters are bad capacitors. You can replace the capacitors on the board and it will work like new again. There are a few specific one's but i am not aware of which because i hate cathodes, therefore i do not do the LS units. Go to your local electronics supply store (even radio shack in some places is stocked good enough to have them) and match the capacitors you see on your cluster (i'd just do the three largest size capacitors, below that shouldn't be large enough to be in main power lines). Caps are cheap, you can recap the entire unit with a $8 soldering iron and $25 worth of caps if not cheaper.
Screw paying $200 for someone to wrap the cluster in a slippery bag and return it to you where the sun doesn't shine. DIY

They are the cheapest one's to work on because essentially almost no parts are needed, and caps are dirt cheap.
If i had even a microscopic amount of intrest in doing the LS units i'd be a rich man from the markup the thieves make on repairing them.
......and no, i will not do them.
-The O Show.