Diesel for 94 Trooper

I am wondering if there are any diesel engines that will fit into a 94 trooper with a 5 speed. I am very interested switching over to a bio-diesel vehicle and love my Trooper. I am wondering if anyone out there has heard of a diesel engine swap and if so which engines will work (cummins etc). Also if any one has done the swap, maybe you could give me some pointers and things to watch out for. Thanks,
Roy <><

I have a Vauxhall Monterey (rebadged Isuzu Trooper Mark 2 for the UK market) 3.1 Turbo Diesel and so it can be done. This engine is installed from new at the factory.