True but I wouldn't do the belts if they weren't anywhere near being due.
Ahh, I was thinking of the D4.
OP has a D3 so D4 is moot.
The bodies on these are designed to be removed. If going to the trouble of removing though I'd have a long list of other items to check and do at the same time (for me a new torque converter and rear fuel pump timing belts would be definates).
Re your fault lights - really something you should sort to get the best from the vehicle, especially if towing and off roading. Use a GAP Diagnostic IID Tool or a Land Rover specialist to help do so.