severe vibration-need help

[drivfour]

I finally installed the 1996 legacy 4eat with converted #2 speed sensor, converted rear(put 96 rear gear on original limited slip gear set). the speedometer reads correctly and I do not have error codes.
The transmission does not seem to perform right. I am trying to figure out what is not working exactly but here is what I have founfd so far

Terrible vibration at 35-40 mph especially when power is applied- not coasting

shifting from D to 3, there is no difference- seems like overdrive is not engaged

I seem to remember car would free wheel if power was off- does not feel the same
on a slight hill car does not roll back ward at idle


I am looking for help in isolating these issues- I do not want to give up on the automatic

Thanks for help