FT FB1 PDS through aft arc question

This question is in regards to Full Thrust Fleet Book 1.

The Optional Rule on page 4 of FB1 says that weapons with aft firing
arcs
may only fire through the aft arc on any game turn in which the firing
ship
did not use any thrust from its main drive engines.

Okay, I understand that just fine.

Full Thrust 2nd Edition says that PDS may fire through the aft-arc.
I assume that, when combining with the optional rule above, that
PDS may fire through the aft-arc even if the firing ship used thrust
from its main drive engines.

Have I got that right?

There is also the rule that says that Class-1 Beam weapons maybe used
in a limited PDS role.	I assume that you can't use a Class-1 Beam in
its limited PDS role through the aft-arc if the firing ship used thrust
from its main drive engines.

Is this correct?

Finally, near the bottom of page 12 of FB1, it says that PDS may be used
in a limited anti-ship mode.  The million monetary unit question is:
Can PDS be used in anti-ship mode through the aft-arc if the firing
ship used thrust from its main drive engines?

Thanks.

--Greg
gregwong@best.com