help : how to recover funds from old multibit wallet .key file

Quite a few years back I had a few BTC pennies in an old multibit wallet on a desktop which had died of old age. since at the time a few BTC pennies wasn't worth the trouble I let it die in peace but kept the carcass thinking that if one day it will be worth it I'll have the option of trying to recover them (and prove that keeping all kinds of junk around the house isn't always such a bad thing). anyway a few days back I took advantage of the fact a computer repair guy was at my place for some unrelated issues to ask him to see if maybe he could revive it and after some tinkering I got a few minutes of access to my old desktop (although without internet because it would crash whenever we tried to connect it) and access to my multibit wallet. now since without internet sending the funds to a different address was not an option I did what I thought was the next best thing which was to export the private keys which gave me a .key file which I naively thought would contain a single address and a single private key with which I could access the funds but it turns out it contains quite a lot of addresses (and keys, I presume). my question is: what now? should I simply try each of the addresses on the file to see which contains funds in the correct amount and then try different keys from the file to try and unlock it or is there some logic to this file and there is a faster and easier way? (mind you it's a really old multibit wallet, probably before seed words were even introduced)..