1965cutlassragtop

i feel like my shift points at WOT could be a little sooner, wondering how to correct this.

right now, i think 1st gear waits a bit too long to shift into 2nd with WOT. however, at 3/4 throttle, it's right on, nice and firm right inside the power band. at WOT, it feels like i'm just past the power band when it finally shifts. from a dead stop, if i stuff it to the floor, you can feel it pull pull pull pull, then you notice less of a pull as it reaches the top of the power band (about 5200rpm), then it shifts into second and starts to pull hard again through 2nd. i would like it to pull pull pull pull, shift, and keep on pulling with no lag in between. it almost seems like it just over revs for a second before it shifts from 1st to 2nd. 2nd to 3rd seems fine, doesn't over rev. i would like to eliminate that lag time between 1st & 2nd if possible. as i understand, any change i make will also affect the normal driving shift points as well. so i don't want to have it worse than it is now. 90% of the time it shifts when i want it to, but it's that WOT 1st to 2nd that seems off. am i just being too observant?? too picky?? is there a remedy for this?? i feel like i could shave some time off my quarter mile ET's (if i ever actually run one...LOL). i know i can adjust the modulator screw, but i heard that only changes the firmness of the shifts, not the shift points. i also know i could swap the governer springs, should i go heavier or lighter to achieve a lower shift RPM? any other suggestions would be considered, just trying to get my car as quick as possible....maybe it is what it is and i should stop nit-picking??