93 Accord Vibration after belt replacement

I just replaced the timing belts on my 93 Accord (F22A). I'm now noticing a little vibration that wasn't there before. I followed the manual to the letter about aligning the balance shafts. What was difficult to tell was the rear shaft timing marks were diferrent from the illustration in the manual. I aligned the shaft using what I thought were the correct marks (approx 11 & 5 oclock for lack of a better description.) Could the new belts just need to break in? I'll check the adjustment at my next oil change. Any ideas appreciated

Those belts really don't stretch or anything, so chances are, you didn't align it right.