An ideal curve would be every 2 hours, but if you could get readings at +3, +6 and +9 that would be great. PZI is supposed to reach "nadir" at +6, so assuming that's what is happening with Scamper, you should get a starting number, a +3 snapshot that would show the insulin starting to work at the same time the food is keeping the number elevated, then at +6 you should see how much the insulin is pushing it down. At +9 it should be somewhat higher as the insulin starts to wear off, and then just before the PM meal, it should no longer be supressing his BG. Then the whole 12 hour dance starts over.
Make sure to test before feeding, and then let him eat, and shoot insulin soon after he finishes eating. You can give him more food during the first 6 hours after a shot, but you should avoid feeding after +6 if at all possible. This assumes he's on a 2x per day feeding schedule of course. Other people can advise on what to and when to feed if he's one of those "eat many small portions a day" kitties. Bob eats twice a day, with a snack or two along the way.
That 3-6-9-12 schedule assumes that you are able to test at those times. On a day off, it might be possible and any time I tried to run a curve, I did it on a day where I didn't have to work or be anywhere else all day. During a "normal" day in your life, any tests you can do beyond the AMPS and PMPS will be beneficial. It'll give you a better picture of what the doses are doing for Scamper, and it will allow people who are looking at your data and trying to help you a better picture too.
Carl in SC