how to change the subtype of replica of blog plugin

Hi all,

I have three replicas of elgg's blog plugin which i created by replacing "blog" with "poem", "story" and "article" these are 3 independent plugins made by changing the word blog to respective names, poem, story and article

I want to convert the subtype=>'poem' to 'blog' so that i can delete the mod poem and all poem will be listed under blogs. Is this possible?

Also if it is possible to add a specific category tag to the converted blogs from poem?

thank you.