Hi Mary
Moving from 5.3 to 10.x will be a migration not an upgrade. You are moving from java base back to ABAP stack.
If you build a 10.x environment for 10.x you could activate the BC sets which contain the ruleset and then download them to file. After that you could compare off-system to the 5.3 rule set.
If the system is your development box and you do not want to use the SAP standard ruleset but retain the 5.3 you could delete the ruleset in 10.x (via IMG step there is a delete)
Regards
Colleen