Don't do more work than you have to, Yes. Figure out where the leak is before you tear into the engine. Maybe a head gasket change will fix the problem, for example. Have you looked at the spark plugs? If coolant is getting into a cylinder, that plug will look unusual, probably very clean.
I can't tell you how many times I've assumed the worst and made myself extra work, but now that I'm almost 60 I do it slightly less often.
