Thanks Ian,
I've already decieded to go with a perkins phasor/5-speed box straight from a dodge 50 as both cheap and plentyfull just like 70s landcruisers over there in oz by the sounds of it.
After a brief 'measure up' it looks as though this set up will fit straight in place of the original lump and enable me to have a reasonably original and un-butchered truck which is twice as reliable and economical!!!
regards
ben.