Tires shudder in turns

I seem to have trouble in turns, the steering wheel starts to shake and the car is not too easy to turn.

The car is fine under braking, no steering wheel shake at all, and the tires are brand new, although the previous owner mounted thhe rims backwards. I am thinking the tires were put on correctly just on the wrong rim.

Also, can anyone tell me how to get a shop manual for the SVX?? I tried Chilton's but there was nothing specific on the SVX, just a manual for all Subarus for certain model years.....anyone know how I can get a good one for my 95??

Thanks