Can't get Battle Walkers upgrade

[getch]

I have finished the game and gotten all 3 contraptions.
I have upgraded the other 2, but I can't get the stamina upgrade for the Battle Walkers.
After checking guides it seems you get it from the quests with Stubbins.
I have done that quest already.

Is it bugged, or am I missing something?

[ksurl]

can you tell me where the constrictor harness and ramshackle are?

[mavrose7]

Originally posted by ksurl:

can you tell me where the constrictor harness and ramshackle are?

https://www.youtube.com/watch?v=ZLHKy7lVWFs