Jim,
You can't use the radio without a licence. The only licence you could get is an amateur radio licence which would let you use the C4x but not the 88, if it is an 88 I saw.
The amateur licence nowadays comes in three levels, foundation, intermediate and full. Each step up gives you more privileges, power levels, frequencies etc. The foundation licence is limited to 10 watts which means you would only be able to use the low power setting of your C4x. The good news is that you can do a short course with most amateur radio clubs and take the exam, often all within one weekend. There is next to no radio knowledge required at foundation level, it is more about operating safely. Be aware that there is debate about foundation licencees using ex-mil equipment, so claim it is not allowed. Best to put a bit of effort in and do the intermediate licence as well.
I should also point out that the Cxx is not the best choice for either talking to your chums in their vehicles, or amateur radio in general as it is AM (amplitude modulated) which is old technology and it will only talk to other radios of a similar vintage. This is a bit of a generalisation but you get my drift. Most Clansman is FM as is all amateur gear nowadays for short range work. And Clansman won't flatten your batteries when static!
Have a google for amateur radio clubs in your area and get in touch with some.
Myself, I have a full licence and an interest in WW2 kit which is compatable with the C4x, hence my interest if you should want to get rid of it.
Regards,
Gordon