If your BJ60 is well maintained, it’s probably as reliable as many new 4x4 if not more. Certainly not as confortable but I think it is not too bad, don’t really need axle modifications.
I use to work with engine which have 50k and 80k hours. They are rebuild at 10k hours intervals.
I think those old LC could run forever with proper maintenance and good quality parts. The only main issue I’m thinking is rust.
I hate how uncomfortable mine is.