We reached a mutual understanding. I wouldn't push him too much; he would occasionally let me pet him or put him in a harness. Last winter, Sundin showed me that he does trust me when he has to, like when he's badly injured and needs assistance. He knows who to turn to when he needs help. After he had recovered, our relationship returned to it's status quo.
Until three weeks ago, when something went click in Sundin's little canine brain. All of the sudden, he decided that he likes me; he likes sleeping in the house; he loves having his ears scratched and he'll run every time I hook a team up. I even get the occasional little kiss while I'm putting his harness on! He can be loose in different pens; I can catch him without trapping him or luring him with food. Like a normal dog, "Come here, Sundin" actually gets him to come here!
Apparently it takes four years, three months and two weeks for Sundin to unpack and decide to make himself at home! I just wish I knew what it was that made the click happen! I would have done it a long time ago!