Doc's Secret Plan.. help

[Omniforce]

I've beaten this quest... but it won't let me go back into it so the guy can turn my junk into weapons. Wha's up widdat?

[TeamPhalanx]

Montague changes parts into weapons in either Dr. Osto's Research or Unsealed Doors. The criteria being that you complete Doc's Secret Plan.

[Orange_Coconut]

In order to be able to replay that quest you must complete all quests first, then you can go back through quests and do as you please. For example changing enemy parts into weapons (as you said
), or maybe you want the Soul Eater, or maybe Akiko's Frying Pan, or maybe you just wanna learn more about the story, get the GBA dl for the Chao Garden.... There are many things you can do once you have completed all missions.