simple byte swap , but what have i missed getting rubbish o0n the word variable

Code:
  SDC_buffer[250] = GateID_word.lowbyte[T*2+1]  'indexed highbyte                       ' copy the varables to tmp varable   
             SDC_buffer[251] = GateID_word.lowbyte[T*2]    'indexed lowbyte                             
             SDC_buffer[252] = Gate_CH_V_Num[T] 
             SDC_buffer[253] = Gate_RX_Sens_Trig[T]    
             SDC_buffer[254] = Gate_Prod_Bat_Lvl[T]                                                   
             
             GateID_word[T]       = GateID_word[T+1]                          ' copy index varables to neighbors next index  
             Gate_CH_V_Num[T]     = Gate_CH_V_Num[T+1] 
             Gate_RX_Sens_Trig[T] = Gate_RX_Sens_Trig[T+1]    
             Gate_Prod_Bat_Lvl[T] = Gate_Prod_Bat_Lvl[T+1]          
          
             GateID_word.lowbyte[(T*2+1)+1] = SDC_buffer[250]   ' indexed highbyte +1                  ' copy temp varables to next index  
             GateID_word.lowbyte[(T*2)  +1] = SDC_buffer[251]   ' indexed lowbyte  +1                      
             Gate_CH_V_Num[T+1]      = SDC_buffer[252]  
             Gate_RX_Sens_Trig[T+1]  = SDC_buffer[253]      
             Gate_Prod_Bat_Lvl[T+1]  = SDC_buffer[254]