Would you trust taking this car on a high mileage drive?

I have a 2005 ford f150. 4 wheel drive 5.4 v8. It has 260,000 miles. So far I've put a rebuilt engine in (20,000 ago) changed the oil, tires, alignment, tie rod, alternator, coolant flush, driveshaft/u-joint, a coil pack, previous owner did trans fluid. The truck is running absolutely fine and I have been treating it like new since I got it. Me and a few friends are taking it approx 250 miles (there and back) on Friday. I just hope it makes it because we will be out of state and kind of in the middle of nowhere. 260,000 is a lot of miles. I feel like it would make it there and back but what do you guys think?

Yeah but have the suspension, brakes and cooling/oil cooler/transmission lines and hoses inspected before you go.

125 miles, and out of state seems ok, in the middle of nowhere, not good, you want to have backup plan no matter, you culd park it and walk, but having insurance or AAA type assistance is fair to have, if just ging fishing, and main road terrain, then ok, if of in desert or rugged ranges, then maybe not too well advised, have you cb, cell phone, map lights, spare wire, tyre, and water to perspire, don't push it.
.

My concern would be for the trans - you would have been wise to have had it rebuilt or exchanged for a rebuilt unit when the engine was done… Make sure you check all 5 tire pressures and hope you have a AAA or similar card

Sounds like it won't even break a sweat. If in doubt, get a boating EPIRB emergency beacon, bring water, food, oil, coolant, tools, spare wheels and tyres, suitable clothing/blankets etc for the weather you expect to encounter.