Re: 1966 problems
Don't get carried away with it, but a quick shot of ethyr (starting fluid) right down the carburetor's throat, if it fires off then you can assure you have a fuel delivery issue. I say don't get carried away because starting fluid has no lubrication properties for your cylinder walls and if you keep on it you'll ruin your engine, 1 quick test for fire won't hurt it.
You should take a look at the plugs before you do anything, are they wet with fuel are they dry and carboned up with soot, maybe all you need is clean plugs. Take a look at the stickies on troubleshooting, you have to cover the basics before asking such a vague question.