At what RPM's should gear shift change during normal driving conditions?

My 1988 - 740 with AF-71 trans seems to shift high. The shift from first to second occurs normally, then takes to around 3200 RPM (42MPH)to shift to third and then again to around 3400 RPM (52 MPH) to shift to overdrive.

Overdrive has been changed at the overdrive solonoid so that so that you don't need to fool with the overdrive button.

Never have been able to adjust the kick-down cable without hard shifts. Currently the cable is disconnected at the same place the throttle cable is connected and has been disconnected for several years. When the AW-71 replaced the ruined original ZF trans., the transmission guy that did the replacement mentioned that the plastic thing that went into the trans. was broken and he glued it back together. I suspect that's the reason the kick-down can't be adjusted. Am not really concerned with kick-down unless it could affect the shifts while disconnected.

Are my shifts to third and overdrive high and could the kick-down affect the shift points when disconnected. The local mechanic wants $500 to replace kick-down cable.

Thanks, James