Are there any differences in the harmonic balancers used in small blocks (excluding the externally-balanced dampers for 400 cranks)?

I'm suspecting the balancer on my L03 may be bad. I plan on using a TCI rattler on the internally balanced 383 I eventually plan on putting in, and will simply buy the balancer a little sooner if it'll fit my poor old L03.

 

Should work fine, the only differences were that the trucks got the larger 8" damper and the cars got the smaller 6 3/4" damper. Also some older model engines had the timing mark at 2 O'clock while I believe most LO3's had it at 12 O'clock. Might want to double check to see what you have. If you have to look behind the water pump to see the timing indicator then it's the 12 O'clock style.

Functionaly, there is no difference between the different sizes.