[Dave at Pelican Parts]

The TDC points for the two fans are the same. Authoritatively. The fans are keyed to the hubs, the hubs are keyed to the crank. There is only one way each goes on, and it's the same way for all Type IVs.

I think it was 8.5 fan blades from the nearest block, but I'm not at *all* sure on that. The D-jet timing mark (27 deg BTDC) is 4 fan blades from the nearest block. But that is NOT the TDC mark. The timing mark is a notch, while the TDC mark is generally a dot or a '0'.

--DD