Yann,

I guess so, the left and right main weights are never the same. I think however the distance the wheels are from the centre will make it difficult to get an accurate measurement. I think the suspende upside down is probably more accurate.

This method of CG depends a lot on the accuracy of the scales and also the accuracy of the placement of the wheels.
And as I said it is probably overkill for our purposes, but fun to do, and makes CG corrections easier.

Regards,
ps

I cant seem to upload the excel spreadsheet. Any ideas?