Technically you can take a standard mini with no modifications and rally it.
It obviously must be road legal - taxed MOT and insured for use on road rallies. This can be as an extension to your existing insurance, a separate policy for these events or cover arranged by the organisers.
To comply with road rally regulations you may only have four forward facing lights (ie headlights and one pair of spotlights).
Noise is often the other sticking point - it's measured on the exhaust and has to be below a specific db. (Can't remember what it is at the moment). It's worth keeping it standard or upgrading to an RC40. I would avoid anything else.
The regulations state no advertising and white door squares are to be avoided.
As to actual preparation - sump guard is a good idea - getting the exhaust system up as high as possible!
Roll cage although not required is a sensible precaution along with full harness belts. In my car I have full harness belts yet still also retain the standard belts as well. Useful more day to day use. The belts I have came bolts with eyes the bolts replace the exisiting seat belt bolts and the harnesses lock onto the eyes.
Fuses for any extras i.e. map lights, trips etc are easily accessible.
As to bits failing - on an event I've, so far, never had a problem apart from the odd bit of trim disappearing. Afterwards yes..diff failure (big time!!) and coils.
Hope that helps. I expect there will be others with more suggestions.
I also have prepared a Road Rally 1997 mpi car which is to Enduro Rally spec and took part in Lombard Revival Rally and Midsummer Endurance Rally.
A good source of spec is found in the RAC Blue book but there are new regs in 2006.
I take part for the pure enjoyment with the intention of finishing and keep everything simple.
From experience the exhaust is the first to fail so I have 2 tips, metal coat hanger and fit earth strap around pipe.
The other thing I recommend is that before you take part in an event get the tracking set up using professional equipment, it saves your arms and also tyre wear.
