I found a way, although there might be a better method.
int end3 = wks.ncols-2; //Assign a different variable to preferred columns
int end2 = wks.ncols-1;
int end1 = wks.ncols;
wcol(end3)[L]$ = "Pressure"; //Use variables in wcol instead of col
wcol(end2)[L]$ = "Time";
wcol(end1)[L]$ = "Temperature";