Hi Paul,
There are going to be quite a few ways of doing this mapping. In terms of a framework, I might suggest you look at http://www.businessanalysisdistancelearning.com/articles/Fundamentals%20of%20Business%20Analysis.pdf which gives a model of how analysis deliverable components map to each other.
How do you record this information - well if you are using a customisable CASE tool such as CASEWise or ProVision you can create custom fields and objects to record the mapping. If not, some kind of database (Access) could implement the mapping. Failing that, excel or similar will also do the job in a time consuming way.
As well as mapping objectives to requirements to business rules you might want to consider mapping processes to organisation units that use them, the phyisical locations of these organisation units and the data the processes logically require to opperate. There are some other components you might want to consider too andy ou can find a schema of this business model on slide 7 of http://www.businessanalysisdistancelearning.com/articles/The%20Business%20Analyst%20The%20Business%20Model%20and%20the%20Strategy.pdf
You can record this business model in the same was the analysis deliverables models. In fact I have an Access database Business Model set up and populated with some real data from a project I worked on. Will send some screen shots if of interest.
Put these two maps together and you would have a great change impact analysis tool if you get it up and working!
Let me know how you get on.
Guy