How best to file Pedigree Charts & Family Group Sheets in a Notebook?

I have a database of about 8000 names (much of it inherited from a family genealogist). We are currently living full-time in our RV so there is not room for a file cabinet. I am using notebooks right now. I don’t think the notebook numbering system I’m using will work long term as it is probably not static. I print out cascading Pedigree Charts and file them in notebook as Chart 1, Chart 2, etc. I then put the Family Group Sheets behind the Pedigree Chart it appears on. I give a number for each Family Group Sheet as it appears on Pedigree Chart. E.G. 4-2 (Chart 4 and number of Father on Pedigree Chart. I use that number to reference loose documents that concern that family)
But, I now realize that as I add individuals to Pedigree Chart those Reference numbers will change.
Is that clear as mud?!
It is too cumbersome to add a REFN, as a fact, to each individual in my database.
I can use the RIN numbering system, but that is for each individual. There seems to be no way to have a number represent the Family Group Sheet. If there was, then I would use that number to reference documentation, such as Letters and other loose documents that refer to that family.
Again, clear as mud?
Anybody have thoughts as to best set up my numbering system?

Each person in your tree has a unique number applied to them in the RM data base.

I would printout a copy of the names list displaying the RM numbers and use the numbers as the basis for your electronic files or manual files.

Eg if person 7654 has 0001 added as a suffix you have from 76540001 up to 76541000 available for the names of electronic files