Hi. You can not change the type of delivery. But you can change click formula used to generate the link.
The easiest way would be to do something like that. Try to replace:
(type.substr(0, 1) == 'h' ? 'h' : 't')
BTW, you will still get pretty long and strange-looking tracking URL that might look suspicious for your customer. Some SMS providers actually provide you with their own way of tracking SMS links by automatically replacing them with some short URL. Check with your SMS provider if it supports something like that.
For tracking detection, Adobe Campaign embeds Tidy to parse the HTML source and detect the pattern. It lists all the URLs of the content so that they can be tracked individually. Adobe Campaign uses Tidy again to replace the URL (http://myurl.com) with a URL pointing to the Adobe Campaign redirection server.