98 Z28 Harsh 1st to 2nd shift

Hello
I am just beginning to tinker with Transmission in my 98 Z/28. Transmission is fully rebuilt with Corvette Shift Relays, extra clutches, heavy duty bell, wider band and B&W shift kit. The 1st and 2nd shift is harsh at part throttle. This is a daily driver. Transmission man put stock 1st to 2nd spring back in Transmission and didn't help much. Still shifts too hard 1st to second part throttle. Would some one please get me started with this problem?
I will attach HP tuner File. Much Appreciation for help!