Thin round harmonic balancer, and the tiny little 2bbl, that looks like a 1bbl.
If it is a 340 with a steel crank, it will have the same balancer though, but not the 2bbl.......
Best way to tell, is to lay under the car, and look at the block, on the drivers side, right under the freeze plugs. It will say ******** - 318 - **
Or ******** - 360 - **
or ******** - 340 - **
You get the idea.
