step #1) save one of the sketchs as new_sketch or some such
#2) copy over everyting above setup
2a ) compile
#3) copy over everthing in setup
3a compile
#4) create a new void with the second file and name it something
void DisplayLoop (void){
put stuff here
}
in your loop()
call that with
DisplayLoop();
now, any and every variable that you need to take from one to the other has to be declared as a global.
it may not be the best way, or the cleanest, but to get started, it offers you two places to look for issues.