Maybe you should post a simpler example of what you are trying to do.
For example, here is a simple sequence diagram:
http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuIe0qfd9cGM9UIKAIcwPHSKb2iuvYSN5IWg9nGgE2ZOs2XhEEigEBYw6JaQQ2dPs2gWwWbEJy_DIaBGuOTF2vQYWQwVWPAMGd9YJev2RMfAHdsB8nUMGcfS2T0C0
@startuml
participant "First Class" as A << (C,#ADD1B2) >>
participant "Second Class" as B << (C,#ADD1B2) >>
A -> B: call method1
@enduml
And here is a simple class diagram:
http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuKhEIImkLb1ooomgBb5m1d6K51AB5Hov71LiQdHr5TBoymsHs4PSN0wfUIb0dG00
@startuml
class "First Class" as A
A <|-- foo1
A <|-- foo2
@enduml
Mixing both would give something like:
Is this really what you want to do ?
So what we better understand your need, please use some image editor to manually create the diagram you want and post it to https://imgbb.com/
It will really help us!