I have already performed the 3.9 + 3.1.4 integration several times: It requires some work, but it is not voodoo magic by any means.
Could you tell more about this? This what I'm going todo, so I'm interested.
No problem. 
Just give me a day or two, I need to first get back home, and do this procedure all over again, so that I take notes, and dont miss something when retelling it. 
Well, I did something better than what I promised:
I created a simple, but rather lengthy AmigaDOS script that will update a 3.5/9 system to 3.1.4.
It is a quick and dirty hack, but it gets the job done, at least on a clean AmigaOS 3.9 system that I have tested with.
I have handled it to other testers to see if it works for them. And if everything goes well, you will have a way to upgrade your system, and even better than that, you will be able to read the AmigaDOS commands it contains and use a different, much better way to perform the upgrade yourselves.
My idea, if it turns out okay, is to upload it to Aminet so that anyone can use/re-use/read it and understand how the bloody thing works.
