Species clematis, like SAC, are often large and vigorous vines and can grow into trees relatively easily. In my area you see C. armandii, C. montana, tangutica and SAC growing well into trees, simply because they ARE so big and vigorous. And many type 3 clems will work almost as well.

Tangutica and SAC are hard prune vines and yes, the vines DO get tangled with the tree branches, but are not overly difficult to remove at pruning time. Be sure to do your pruning before the tree is budded out or you can possible damage the new growth. And I would take pains to match the tree with the vine so that the tree is large enough and hardy enough to stand up to a mature vine. And that will differ with the type of clem you select.

I have never had the need to use a support system (other than the tree) when doing this but it depends on the clem and how old it is when planted. Some temporary caging or supporting may be necessary but once established in the tree, this is no longer necessary.

You might also want to know that SAC, Clematis terniflora (or incorrectly, C. paniculata), is considered an invasive species in a large part of the country. You might want to check with your state's invasive plants council before planting

If this is an established tree, you will want to plant the clematis a ways from the trunk to reduce root competition, and if it is a newly planted tree, you will also want to wait a couple of years for the roots to get well established before letting the clematis climb it since the tree-clematis can make for a big sail when it's windy. To get a hard prune clematis into a woody plant like a large shrub or tree, I often give it something such as a metal obelisk, a piece of rebar or a bamboo pole to allow the clematis to easily get up into the branches.

I'm in my area there are some wild spruce trees along freeways that have clematis growing up them. Don't know if they're native or invasive here, but beautiful either way