I'm installing the ps control valve onto the drag link (not installed on the car yet). The valve is very hard to thread onto the rod. I put it in a vise and used a pointed bar to rotate it but I can only get it to within about 1/4 inch of all the way on. The bolt went in okay but I'm not sure if I it is centered on the flat part of the threaded area. Is there some play with the flat spot or does it need to be perfect? Does the valve need to go all the way on to the end or is it okay if it is not bottomed out?