Huntandjeep,
Thought I might chime in on your inquiry to see if I can help out. If you have the taxidermist then definely check with him first as Torrent said. If your in the back country and cant get to a freezer or cooler then there are a few tricks that you can do that will help to ensure your cape will make it to the taxi safely. First, properly cape the buck/bull and remove as much meat as you can. If you know how to remove the skin from the head then this is even better; if you've never done this I would HIGHLY suggest to not make this the trip to attempt it, especially if its something your really looking forward to see in a mount. There are tons of YouTube videos on how to remove the cape from the head, however actually doing this step is paramount to doing several at home before attempting in the field. Once you cape the animal lay the skin out, flesh side up, out of the sun, to cool. You don't want to roll the cape up right after you skin it as the hide even holds heat and this rolled up will start to rot quickly. Once the cape and head is off the animal and cooled roll it up skin to skin and put in a BREATHABLE bag, not in a plastic bag! Use this to transport out of the woods and too a cooler, or even better yet, freezer.
If you are in the back country and will be there for a few days following your harvest then there area few tricks. If its freezing out during the night let it freeze and then place out of the sun and in a cold spot during the day. If your near a cold creek take several of the industrial strength black plastic bags and put the cape into one of them and then double bag with the next one. Put the bag in a cold stream, just ensure the cape doesn't come in contact with the water, as the bacteria will promote rot. Snow works the same. I had a customer that shot a dandy mule deer years ago and hiked 1000 feet up to a snow drift and kept his cape packed there for the duration of his trip. Salt should be your LAST resort!!! Most people don't salt correctly, meaning that they don't remove the head from the skin and just salt the back section of the hide which is completely worthless. The head will still rot. Correct salting techniques requires that you remove the hide from the skin, remove ALL flesh, turn at least the ears and lips and then salt liberally. This will only get you by for your trip out, but the cape can still go bad after some time if exposed to any humidity.
Wow, sorry for the book here....hope this helped a little. If you have any questions feel free to give me a call or even better check with your taxidermist. Best of luck to you and have a great time, love Montana!
Joel-BRT