[highperf4x4]

Your engine was hard to crank because the timing was too far advanced. Same goes for the "rattling" noise you heard. It's referred to as "pinging".

If you got a dizzy with an adjustable vacum advance then you will adjust it by sticking the allen wrench that came with the dizzy into the front vacum port for the vacum advance. In other words, you still stick the allen wrench into the same hole you put the vacum hose on. All the way to the left will be no advance and all the way to the right will be full advance. I don't know which dizzy you ordered but most come with a 20 degree vacum advance and the factory jobbers were 10.

However, before you do that, are you sure you have the timing right? You set the timing with the vacum hose disconnected from the advance, the port on the carb plugged and the engine idling at about 800 rpm. 8 degrees initial timing is ok if that's what you actually have. Then you have your mechanical advance and vacum advance. Your mechanical advance should be all in by 3000 unless you went to the stiffer springs. Your dizzy should have come with 3 sets of advance springs unless it was just a stock model. Combined, you want to be under 37 degrees of total advance at 3000 rpm.

Another question is did you regap your spark plugs to .045? With the points dizzy you should have been gapped at .035

I don't know what you tapped into for you hot wire but if you're sure it's got a full 12v then you should be good. If you're not sure, throw a meter on the wire and check it.