Front seat won't lock in place

[TonyM]

After re-installing my original equipment front seat in a stock 1937 Ford, I have discovered that it won't lock in place when adjusted. I took the seat out and observed that the seat handle blade was not falling fully in the notch that would hold it in place. I clamped the combination in place and forced the pieces back to their home positions and it seemed I had solved the problem. Got my car running and when backing into my garage the seat let loose. Lucky for me I was able to maintain control of the car.

I am going to remove the seat soon and try and solve this a second time. Have any members experienced this? I used the search feature to look for previous posts, but came up empty. Looking for any help. I guess I can bolt the seat into a single position, but I want to be able to operate the seat as intended. Looking for any help in solving this problem. Any help greatly appreciated.
Thanks.