I had play problems in my 68 which is the same as the 69 steering system. I spent years and tons of money, and aggravation trying to fix it and I had no success.
I replaced all the tie rods, control valve, installed a flaming river gear box, upper and lower control arms, coil springs, and rag joint.
I even purchased a manual adapter to eliminate the control valve to narrow the problem.
I ended up purchasing a rack and pinion steering system from Randal's rack. Absolutely the best money I ever spent.
I cost me about $1,300 for the rack system, which is about the same as what I spent for all the parts above.
Now the car has absolutely zero play, really made the car a pleasure to dive.
The system was a one day installation. I started at 8 am and had it finished at 5 pm. Then I had to take it in for an alignment.