My new alternator says to make sure to use a resistive type of voltage regulator not the points type.
How can I tell what type I have?

 

The former is electrical, the latter is mechanical.

 

New replacements are almost always electronic and original is points type. If you get a new replacement regulator - which is a good idea anyhow - you should be good to go.

 

The electronic regulator has a thinner cover than the mechanical.
The first picture is electronic, the second mechanical.
Blue and White is correct, you pretty much have to look hard to find a mechanical regulator now days.

 

Thanks Blue and white and Mike