Trumpy,
It is not reccommended or advised to run two sets of meter tails to the feed side of the RCD (or ELCB Earth Leekage Circuit Breaker) the correct way to actually do this is take the meter tails from the load side of the meter then to a 100Amp services block (big bits of terminal block in a rather largish enclosure) then two sets of tails to each service panel.
100Amp is the standard size single phase to a domestic property in the uk.
ryanj.
one thing i would also advise is that you have a qualified electrical contractor perform an Inspection and Test and produce a report on the installlation for you, this will give you a better insight into the condition of the installation, as Paul has said, changing the re wireble fuses to MCBs (miniture circuit breakers) would be a good idea, and testing the RCD would also be a good idea, but if you are unsure consult a Qualified Electrical Contractor.
if you need any further advice just post.
John H