Hi Patel,
I don't think there is any standard way to find that, please understand the logic of the screen as below:
The screen Number 8309 and 8459 are provided by SAP for customer enhancements and it is not touched during upgrades,when we use access key for the same and change then we have to register it in SCCR and we need to take special care for the same during up gradation by informing them.
Please note that SAPMV45A is common for all sales related transactions like VA01, VA41,DP90 etc.
SAPMV45A is the main program for all sales related transactions.
Please let me know if you still have any doubts on the same.
Regards,
Satish