This should be very similar to the lookup that was written for RuleBaseValues except that it will be for the RuleDelegation business object and have the following additional lookup fields:
2) parent rule id (with a lookup icon to the RuleBaseValues lookup)
3) parent responsibility id
You'll notice that RuleDelegation has a delegationRuleBaseValues attribute which points to the actual delegate rule
After you do this, you should be able to remove the "delegate rule" boolean indicator from the main rule search.