Driving with our 2012 S P85 would be similar to the experience with an X 75D (since the dual motors get better range compared with the single motor S).
You will be stopping more frequently with a 75D than if you had a 100D, likely having to stop at every charger, roughly every 150 miles.
If this is your first long distance trip, recommend you use the online route planner tool and/or assemble your own spreadsheet.
When we go on long distance trips, I've created a spreadsheet and planned out our route, and likely charging stops. Based on when we're going to hit superchargers, we'll research the area around the supercharger to find a restaurant when we're near a meal-time - and if you're stopping for a meal, you'll have enough time to get a 90+% charge allowing you to drive a little further after the meal. And for overnight, we'll either stay at a hotel with the destination (or 3rd party) charger, or with a nearby supercharger.
Tesla has been adding enough superchargers, that you may have a few times when you'll have your choice of stopping early or stretching your charge to reach the next supercharger. While most of the superchargers are in decent places, we encountered one that was at a horrible gas station - and vowed to never go back. After that, we did more research on each supercharging stop so we knew what to expect and what to avoid.
For destination or 3rd party chargers we plan to use along the route, we'll consult plugshare to see if there were any negative comments (like one hotel we used claimed to have 4 destination chargers, but 3 of them were blocked by a skid and not easily accessible). And if we aren't confident about it, we'll check with the hotel staff to verify access/availability of the chargers. Especially in smaller towns with few (if any) alternate charging options, you want to have confidence you'll be able to charge overnight.
When stopping overnight, always charge to 90%, unless your route planning indicates you'll need more than 90% to reach your next charging stop. Unnecessarily charging to 100%, especially if you leave it at 100% for several hours, risks long term degradation of the battery pack. Plus if you overcharge overnight, since charging is much faster when the battery pack is at low charge, you'll save very little time at your first charging stop if you unnecessarily charge to 100%, when 90% would have been fine.
You shouldn't need a CHADEMO adapter. Make sure you have your Tesla UMC, with the supplied 110 and 14-50 adapters, plus the J1772 adapter for using 3rd party chargers. Plus, if you're going to be visiting or staying with family, you may also want to get a 14-30 adapter to use with their dryer outlet.
Additional items you should have - paper towels, glass cleaner, tire pump, and tire repair foam. Since you won't be stopping at gas stations, you'll need to bring your glass cleaning supplies with you. Tesla sells a tire pump with the repair foam; the pump will let you add air back into the tires during your trip (which may be useful if facing major temperature changes during the trip). The tire foam is a last resort, if you get a flat tire, and Tesla isn't able to get someone to you to help in a reasonable time frame.
On our first long road trip with our S P85, it was an adventure - 1100 miles with one overnight stop. We took photos at each charging stop (think there were around 10) and texted them to family. And after that trip, and we got used to the drive/charge/drive strategy for long distance EV driving, it's no longer a big deal - and Tesla has since added many new superchargers and destination chargers, making this much easier.
One last piece of advice, while the onboard software does a pretty good job of projecting the charging stops and the estimated charge you'll have at the next stop, you should still monitor your discharge rate by periodically checking the estimated charge at the next stop. When we see that charge moving to 10%, especially when we're still far from the charge stop, we'll start slowing down a little and build back a larger cushion - rather than waiting until the software tells us to slow down below 60 MPH.
Driving a long range EV on a road trip is a different experience. It will take longer, because the charging stops during the day take longer than a gas station, and you'll likely need more charging stops than you would take gas stops in an ICE. However, we've found the drives are much more relaxing. The AP2 software does a pretty decent job in handling most of the driving. The onboard navigation software tracks our route and warns us of traffic issues (rerouting, if needed). And stopping every 2.5 to 3 hours for 20-30 minutes provides us time to relax, hit the restrooms, get something to eat/drink, check our e-mail and then get back to driving for the next stretch.
