[HTTPS-Everywhere] Private/personal ruleset location?

[J.B. Nicholson-Owens]

[To those of you on the HTTPS-Everywhere-rules list, my apology for 
posting this twice -- once on the -rules mailing list and once here.  I 
didn't realize I first posted this to the wrong mailing list.]

I have a few rulesets I use but I have no desire to upload to this list 
for others to use. Some are for private websites others can't reach, 
some are experimental and I'm working on.

Where should I put my private rulesets so they'll still be around when I 
update the addon? I am trying to avoid losing my rulesets by deletion or 
overwriting.

Is there a directory where users can put rulesets that always trump the 
rulesets in HTTPSEverywhereUserRules (should a ruleset filename be the 
same)?

Thanks.