[Tomy Awards]

I am just getting started with calibre and ebooks, and have come across a question I have not found yet in the forum.
I am trying to create a series of several ebooks that will all have exactly the same layout. The only differences will be their cover images, titles, the text on the pages, and the number of the pages. Otherwise they are the same.
It took some time to get the doc to epub conversion to look like I want it, so I would like to use the first one as a 'template' for the others and just change the text and cover images. Is there any way to overwrite and do a 'save-as' type of conversion on the first one?
I tried saving the file to disk, renaming it and then putting it into the calibre editor but it seems to retain the original title as part of the title bar, along with the new one. The cover image also seems to be hard to replace.
I also tried copying the entire folder and renaming it and then worked out of that folder, but it still seem to have some old data in the file. I have altered the metadata and copied the new cover image into that new folder but it still shows the old image as its cover.
Any ideas as to what I can do for this to work - it would really be a timesaver if possible. Maybe there is a function I don't understand or there is a plugin that might do this... I'm just not sure.
Thanks for any help you can give.