TH400 shift points

[AlienYouth]

I'm running a TH400 in my truck and need to raise my 1-2 shift point, I was told that a TH400 shifts at 4800 RPM 1-2, so does that mean playing with weights in the governor cant raise my shift point, or is that just what it normally shifts at? I've never been too deep into my tranny, so i figured i would just ask before i start messing with stuff. Will I have to buy a manual valvebody, and are the "manual/Automatic" valve bodies on Summit really fully manual for the 1-2 shift, or do i just need to play with the governor..? I kinda like not havin to screw with my shifter when cruisin around in my street truck wit bench seats and the ladyfriend...

Thanks in advance