A-727 Kickdown

I've been trying to get my kickdown to engage passing gear to no avail. I checked the linkage connected to the carb and everything lines up perfectly at idle and WOT. However, I noticed that the kickdown lever connected to the trans has no spring load whatsoever to keep it in the forward position. What's the easy fix here? Hoping this has not caused any major damage since I've noticed a vibration and knocking on the transmission tunnel at idle, at various speeds/rpm's and for a split second when giving the vehicle throttle and letting off the throttle at cruising speeds.