Is there a way to tell if the tach is reading the correct RPM? I used a tach and dwell meter from a friend, but it is pretty old and I don't know if it's accurate. That being said, it was 200rpm lower on the read out than the tach. I just have a Sun Pro old school look tach. Are there any tachs that are dead on from the get go? Thanks.

You could use a timing light with a rpm readout. That will let you know but they are a bit pricey.