Use portable SeaMonkey with non-portable SeaMonkey

I have yet to try, as I'm worried about what could happen.

I want to use a Full Install of SeaMonkey at the same time as my Portable SeaMonkey- both open at the same time and being tweaked concurrently.

I tried a search, found nothing recent.

My reasons for this:

I want to make a 100% standard theme for SeaMonkey that I can use in my Portable Version. Eventually, I would like to approach somebody about including it somehow.

If nothing else, I would like to learn more from the experience about portablizing apps.

Thank you for any and all guidance on this!