Although I do extensive A/C work as a DIYer, I had refrigeration training many years ago in conjuction with some instrumentation work that I was doing. In addition to that, as a youth, I helped my Dad with air conditioning work. He took a three day course in about 1956 when there was a hot market for aftermarket auto air conditioning. He made a good supplemental income installing auto air conditioners after regular shop hours. I remember he said that he could clear about $50 and could usually install one in an evening after closing the shop. $50 was quite a bit of cash in 1956, when soft drinks and candy bars were a nickel. I was only seven, so I don't know the costs of anything else, except that one dollar was an enormous amount of money.
I believe that the flag that triggered Steves appropriate response was two fold; you were talking about using the changeover kit AND you didn't know how to identify the high and low side. If you have even a very basic knowledge of refrigeration, you can examine ANY refrigeration system and identify the high and low side.
I expect that most community colleges have some good continuing education courses on refrigeration. It's not a difficult thing to learn, but as Steve pointed out, it is important to know what you're doing for personal safety as well as to ensure that you don't make things worse on the equipment that you touch.