I have been part of the DeTomaso Family for over 20 years.
I have seen very few discussions on the dipstick as it is so very uncommon.
what I have seen is numerous discussions that filling to the bottom threads and then checking the level after a drive, (because there are some sections that are apparently connected by holes as opposed to being one large section) is the recommended approach.
works for me, and every other owner that I know of.
Larry