If you have the Optional Paper Cassette #2, install it by:

[Tofu]

Hello Alan, Mister Micawber, Beeesneees, Mordant, Esl_Expert and other native English speakers,

---------------------------------------------
http://tinyurl.com/2femaud
If you have the Optional Paper Cassette #2, install it by:
A. Carefully pick up the machine and place it on top of Paper Cassette #2.
B. Plug the modular cable from Cassette #2 into the modular jack on the Brother machine.
---------------------------------------------

Is by fine as it is? What about "in the following steps"?

[Mordant]

I would amend A and B by making the finite verbs gerunds. A main verb cannot be a prepositional object.

[Tofu]

"A. Carefully pick..." ---> "A. Carefully picking..."
"B. Plug..." ---> "B. Pluging..."

Correct?

[Mordant]

Yes, but also add "placing." That's two g's for "plugging."

[Tofu]

Thank you, Mordant.

1.
If you have the Optional Paper Cassette #2, install it by:
A. Carefully picking up the machine and placing it on top of Paper Cassette #2.
B. Plugging the modular cable from Cassette #2 into the modular jack on the Brother machine.

2.
If you have the Optional Paper Cassette #2, install it in the following steps:
A. Carefully pick up the machine and place it on top of Paper Cassette #2.
B. Plug the modular cable from Cassette #2 into the modular jack on the Brother machine.

Is #2 good as well?

[Mordant]

I find no fault with the second option.