When in Rome, do as the Romans do. Glad that you respect local customs by asking and checking first.

"DJones said ...I DO want to gauge excatly how severe/negative the response would be if I did, say, decide to travel to the beach in a pair of shorts and a tank top with bikini underneath."

- No problem. Have a shawl or some loose piece of clothing to cover up while you're traveling to the beach (in case you have to get out of your car or be out in public - where modest dressing is expected and keeping a low profile is generally a safer bet). Shorts and tank tops are acceptable beachwear.(NB: I said "beachwear" and in the privacy of homes but not in public) Bikinis are fine for the beach too, depending on which beach - preferably not the isolated ones or you'll have a bit too much attention of the wrong kind.

"Some of the clothing I own (and love!)now I wouldn't DREAM of wearing out there. I'd probably be deported... :P BUT, I was at least hoping to hear that some people do still keep some of their original dress habits without too much backlash."
- Yes, but you need to be alert and aware of your surroundings.

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Don't want no drama,
No, no drama, no, no, no, no drama