[Q] how do i replace the stock sms app with go sms pro? topic

i want to replace the stock sms app on my k900 with go sms pro. how do i do this? i've already checked in the go sms app that it be the default messaging app but i still get double sms notifications and the stock sms app is still active. i can't find anything in the system or messaging settings that would normally turn off the notifications for the stock sms app just like in my past htc's and xperias.

any help would be greatly appreciated.