301 redirect / mod rewrite help please

I'm in the process of migrating one of my vB 3.8 forums to Xenforo. I will be importing all the data into a clean install, so the thread and post IDs will remain the same. I need some help with mod rewrite rule(s) that would cover the following:

Old:  www.domain.com/forums/f23/thread-title-1255/
New:  www.domain.com/threads/thread-title.1255/

Old: www.domain.com/forums/f23/thread-title-1255/index2.html
New: www.domain.com/threads/thread-title.1255/page-2

Old:...

Code (markup):

301 redirect / mod rewrite help please

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