What all can be done to the 29 XL led

I know this isnt the answer you are looking for , Craig covered that pretty good, but I would leave it stock except for maybe having the AMC turned up to 100%, it should then be deadkeying around 4 watts and pep swing to 16watts. I know that doesnt sound real impressive, but with a good antenna system ( more critical than the wattage) you will be surprised with your transmit and recieve range. If after a while you feel the need to stepup to more wattage and more features purchase a radio like the Stryker 955 ( just chose it as an example) that comes stock with 16 watt carrier and pep swing to 60 - 70 watts, talback,echo,bands,SSB, then you can use the Cobra as a good backup and you will own two radios that are stock and unmolested, by the way you will have to have the 955 or any other 10meter export converted to 11 meter which is usually done by the seller. Hopethis helps.

 

90% modulation sounds and performs twice as good as 101% modulation.
If tampered with, I hope the guy has an accurate bench to avoid going too far.