The changes in trim might be too subtle to measure, unless you have significant differences in the wings.
With the same chord, a short span, medium span and long span would appear to permit the changes in trim to be observed, but it won't be much from one to the next as the c.g. will be the same.
You would need to measure the speed as well as record the trims for each plane. That will be the most significant change between wings.
This photo plane with any of these wings flies pretty much the same.