How to display one single post on different pages using different layouts?

Hello,

For the purpose of my website I need to display one single post on two (preferable three) pages in different layouts. These layouts need to differ in size, custom fields they display and the layout of the page surrounding them. I got the different themes, different showing custom fields working when showing all posts, but when I try to open a single post is always goes back to one theme.

I tried to use category themes by posting in two categories and hoped that if wordpress loaded it starting from a different category it would use a different theme, but WordPress always chooses one when going to a single post that uses more than one category. I tried to load different ones by making my website save posts by “category name/post name” and then make an iframe opening that URL address but that doesn’t work either.

With the amount of custom fields used and the quantity of posts every day, it would be undoable to post it twice in different databases/wordpress accounts with different custom fields.

One thing I thought that could help is a php-script that reads the used URL and chooses the layout by looking at if the post is loaded from ‘category-1/post name’ or ‘category-2/post name’. That way I could load it from an iframe using ‘mysite.com/category1/post name’ on page nr.1 and from category2/post name on page 2.
2nd thing I thought of,was to make the post load trough a certain php file, but I don’t know if either one of that is possible. I really hope someone can help me. If anything is unclear please tell me so I can try to explain. I appreciate any help you can give me.

Yours sincerely,
Marc