No, not really "paying taxes" and all that stuff. Just giving the OP something to consider since he indicated he wanted to "make darn sure I'm not setting myself up for a world of legal hurt." The PA LTCF is familiar to most PPD cops, it would minimize the likelihood of ending up in the the type of situation the men in the article I linked to did. As a up-til-recently resident of Philly, I wanted to give him a "heads up" on the current climate regarding out-of-state licenses (often called "Florida loophole" licenses by the media demonizing them, since many Philadelphia residents carry on a Florida license rather than run the PPD LTCF application gauntlet) so that he might make an informed decision.
I myself carried on a Non-Resident LTCF from another state during my time in Philadelphia. PA recognizes certain Non-Resident state LTCF's, and rather than go through the PPD process, I just kept my Non-Resident current (to include updating it with my Philly address) the whole time I lived there. I also had an attorney on retainer, knew the laws, and had accepted the possibility of being inconvenienced by my decision. As well, I moved out of the city as soon as I could, since the civil rights violations happening in the city of Philly don't stop at their unlawful restrictions on gun ownership.
Forewarned is forearmed. If the OP wants to "stand up against government entities including police that would, via threat of arrest, force their opinions unlawfully upon that citizen", and has the time/money/motivation to do so, then at least he knows that Philly might be a good place to do that. Go to Reading Terminal Market for lunch, get "bump frisked" walking past a cop, pretextually stopped, and end up explaining your out-of-state LTCF to him. At least you would know that's what the PPD is up to recently, and would be prepared for that eventuality.
If worrying about the possibility of explaining his Indiana LTCF to a less-than-sympathetic cop under orders from a gun-grabbing administration to "get guns off the street" would ruin his weekend visiting his friend, the OP's personal risk/reward tolerance might have him reconsidering his plans of traveling with his guns. Of course, this might lead to him worrying about getting assaulted while unarmed, a real possibility in "Killadelphia". I don't know the OP, and he'll have to make this decision for himself. In any case, the more information he has the better situated he is to make a decision befitting his own circumstance, or at least pre-plan his trip, which is what I understood the OP was looking for.
