External Error Pages?

[mudkipper]

Hello,

I want to use the error pages for my website in place of the error pages for vbulletin (primarily 404) as i want to be able to have a consistant feel across the site. I have seen this mod:

https://vborg.vbsupport.ru/showthread.php?t=231843

but that is not the way i want it, that is vbulletin - > webserver error pages, i want webserver -> vbulletin webpages.

Also i find that from old indexes on google from the previous site owner, the links dont return a 404 so the links dont get removed from google as they need the 404 error code to remove links in the index - this is why i want to use my own http error pages aswell.

Any ideas?