Firstly, if the engine is in safe mode, you can turn all these sprockets to your hearts delight, the pistons are halfway, and will never touch.
I don't even know (can't remember) if you have to loosen the bolt to get the belt off, but it is possible you have. but with the bolt in place you can get the exact position by putting a wrench on the bolt and moving it here.
The torque on these bolts is stupid high, I must admit, I don't know why, but I would imagine it has a lot to do with old days, and fearing a bolt coming loose owing to vibration.
I always use a bit of Loctite on bolts such as these and even the pulley bolt, and I give them a good torque, but nowhere what is recommended. The Loctite will make sure they go nowhere.
Three teeth, possible valve interference on some of the valves. You can pick that up on the cam followers/lifters. A bent valve will normally not close fully, even when the cam is off contact. Any lifter that does not come to the top when the cam is off, is suspect.
Good luck.
Oh, and to anticipate a future question, the answer is NON.
What is the question?
The belt looks very slack, so new ones are required, no doubt.