Aligment of adaptor plate , flywheel and flywheel housing on Perkins 4.108?

[pr2501]

Before I start I need to clear some facts. I was reading the workshop manual. (page 84. and 85.)

I can center the flywheel ( fig. 2) and flywheel housing bore ( fig. 4 ) . But how can I change the situation of flywheel face and flywheel housing face (fig. 1 and fig 3. ) ?

I have the clock gauge. If I understand right I will have just to fix clock to adapter plate and measure the flywheel while rotating of crank shaft. Flywheel bolts have some play what permit regulation of position. Once flywheel is in the center I have to fix clock with magnet base on flywheel and align the flywheel housing by rotating of crank shaft again.

Am I understanding it right?