I have a front seal oil leak and tried to replace the front seals. I encountered the following problems. I positioned the crankshaft seal too far in, so it leaked. However, I can't get the seal out. How do I remove this seal?

I checked the tension in the bolts for all of the sprockets and found them loose. I used a torque wrench, but suspect that the timing belt moved while I was torquing it. How do I tighten the sprocket bolts properly?

The crankshaft has a gear with a notch on one surface. Does that notch, that protrudes out, hold the harmonic balancer?

Thanks in advance.