Milsey I am not sure from your postings, whether you are aware of the JAR requirements prior to get an instructor's ticket. If you wish to be paid for instructing, then for most intents & purposes, you have to do the CPL, before the instructor's course.
You can get an instructor's rating with just a PPL, BUT you cannot then be paid in any way, for instructing.
Others, far more knowlegable than me, have recommended that there is little point in doing the CPL ground exams. You might as well do the ATPL's as they do not involve very much more & will save you having to do a lot of the papers twice. Also, most FTO's are now only offering courses for the ATPL ground exams, due to lack of demand for the CPLs.
If the above is not clear, please post another message, & I will leave the experts, on this forum, to reply.