When u all buy Suncoast kits such as the level 3, do u install them? or do u take them to a transmission shop

You can do it yourself. If you have some mechanical ability you should be able to manage. Read my other threads in this and the OEM allison forum for some of my notes. I just finished mine today. If you are sqeemish don't attempt it yourself. Something about tearing into the transmission on your 50k truck is hard on the nerves. :D