The manual is not very clear about getting the draft control to work. I had to use the service manual from the F series and the 25 series and cross the info to get the draft control to work.
The manual mostly says to unlock the draft control by flipping the little tab on top (#1 on the picture). However, one needs to move a plate (#2) behind the top link mount so this mount can travel back and forth to activate the draft control.
That bigger plate (#2) comes in the middle on the two shims (#3) from factory. This still blocks the movement of the top link mount. So this plate needs to be moves further back, as I did on the picture, so it allows the mount to pivot in and out. At first, I thought these bigger plate was like a spring, but that wasn't the case.
By the way, the two bolts holding the plate and shims are very very tight. Those are accessible with a wrench from the side or with a socket from the front. I recommend the socket as it reduces the chances of stripping the head of the bolt. The size I believe is either 12 or 14 mm.
Here is a picture I made for reference:
View attachment 706097
Let me know if you need more help. I can take more pictures if needed.