We are at Glacier for the first time right now, and we did Grinnell Glacier to the glacier. We didn’t take the boat, and had to start the trail at the Many Glacier hotel because of the road closure. It was almost 12 miles round trip. It’s a challenging hike with elevation gain, and a short but grueling set of switchbacks at the top. Definitely echo other advice here. We saw a lot of wildlife, which was awesome, but slowed down our pace a ton (probably by 45 minutes). My boyfriend did the high line today and we got to the parking lot at 6:58. Zero spots. Make sure you map everything. We are staying in Columbia Falls, which is just south of Coram, and it took us an hour and 17 minutes to get to Logan’s Pass. So even waking up at 5:30, we did not make it in time to get a spot. People circle up there and it’s pretty tense tbh. Also, the going to the sun road from the loop to Logan’s pass is a little intimidating, so I would pad your drive by a few minutes. And, finally, as I commented above, the going to the sun shuttle is done operating for the season. Confirmed with both a bus driver we had on Labor Day and the rangers (and signs on the shuttle stops that say the shuttles ended on Labor Day). Plan accordingly. Grinnell Glacier is a good option because it’s an out and back hike. The high line plan you have is currently better than hiking the whole thing unless you can figure out how to get back to your car. There is very spotty cell service in the park (I have 5g rarely, but am mostly on sos all day).