I have been given a Hitec Challenger 260 TX, with a HP-2RNB RX. Both are set for 29MHz spectrum.

My questions are:
1. Where can I obtain a manual for this unit? Even a soft copy would be good. I don't have any obvious need for it, but I always like to have the manuals handy.

2. Where can I obtain a replacement wheel, as the existing one is a little worn?

3. Is it possible to convert the TX & RX to use a different spectrum, as I believe 29MHz is designated for air, and I run mainly cars, along with an occasional boat? If so, is it as simple as changing the x'tals, or does it entail something more?

4. Is it possible to replace the antenna wire on the RX? What is required?

Please bear in mind that I am in Australia, which means shipping anything to/from the US or Canada is excessively expensive.