Early V8 Distributors

[motordr]

If one was to build a stock 1936 LB engine with domed pistons and cast iron 68 series heads would bolting on an early 40 series distributor be a step backwards?
The advance curves appear similar yet the 68 or 78 series distributors have a better design advance weight mechanism. Also the rotor is smaller diameter on the later distributor.
Anyone have “ real world” experience with this? This is going into a 32 Fordor. Thanks!