72 + 340 motor

And since this is a cheapo effort.....

You can see how big the weight is here, as well as get an idea of how far out from the center this type of weight would set from the the placing of the bolt holes. The small weight is for the late 340 and bolts to the back of an otherwise balanced damper for a 318. http://professional-products.com/me...78eab33525d08d6e5fb8d27136e95/9/0/90012_1.png

Here is the same but cheaper: https://www.amazon.com/dp/B004BTB4VU/?tag=joeychgo-20

These particular weights bolt on the back side of the hub, so you have to mentally flip the weight over in these pix to figure them out.

To put this type of weight at the right angle relative to the keyway, you can look for a pix of a stock late 340 damper on this site or elsewhere and center it at exactly the same angle as the 'cast weight on the original damper shown here: https://picclick.com/Mopar-340-Plymouth-Dodge-Cast-Crank-Harmonic-Balancer-322421913680.html