The timing mark should go all the way across the balancer. I really don't know much about those but found this in my Ford manual on the 3.0 distributor ignition
CAUTION:
Do not use a remote starter while doing timing check.
l Key off.
l Install timing light.
l Remove SPOUT in line connector.
l Run engine at normal operating condition.
l Is base timing within ±3 degrees of specified base timing?
Here's another note to it
Preliminary Note
The procedure described below for setting initial timing is to be used under normal circumstances.
This procedure is for Distributor Ignition systems only. EI low data rate and high data rate systems cannot be adjusted.
³ Procedure ³
³ 1. Place transmission in PARK or NEUTRAL, A/C and heater in OFF position. ³
³ 2. Connect an inductive timing light, Rotunda 059-00006 or equivalent. ³
³ 3. Disconnect the single wire in-line SPOUT connector or remove the shorting bar from the double ³
³ wire SPOUT connector. ³
³ 4. Start the engine and allow it to warm up to operating temperature. To set timing correctly, a ³
³ remote starter should not be used. Use the ignition key only to start the vehicle. Disconnecting ³
³ the start wire at the starter relay will cause ICM to revert to start mode timing after the ³
³ vehicle is started. Reconnecting the start wire after the vehicle is running will not correct ³
³ the timing. ³
³ 5. With engine at timing rpm if specified, check/adjust initial timing to specification. ³
³ 6. Reconnect single wire in-line SPOUT connector or reinstall the shorting bar on the double ³
³ wire SPOUT connector. Check timing advance to verify distributor is advancing beyond the initial ³
³ setting. If it is not, refer to Section 2A, Quick Test. ³
³ 7. Remove test instruments. ³