Most roads in the UK* aren't as rough as stuff like the Silk Road though, Shayne, and even if you do break down in the UK, recovery is straightforward. On bigger trips you are reliant on the vehicle, your own skills and whatever local help is available.
That said, I don't see the need for massive modifications for big cross country trips - its more a question of making sure everything is spot on before you leave (baselining if you like) - keeping stuff stock also helps when sourcing spares, if you do breakdown. Heavy modification is more necessary for severe off-roading (i.e. playing), rather than bad-roading and over-landing, I would suggest.
Raj - you shouldn't need to be fighting your Cruiser in the corners, Jan drives our 80 like she stole it, even with some health issues, and it handles well.
* - though the IOM roads are essentially like those in the Third World!