MY OWN QUARTZ OR THE CLOCK SIGNAL FOR MY EXPANSION CARD ?

I am dreaming about making a coprocessor expansion card for my Apple//gs.

In the case of the Microsoft Z80 expansion card, does the Z80 has its own quartz on the card
or does it only use the clock signal from the slot of the Apple//gs ?

With my cousin electrotechnician, we do not have a "insoleuse double face" (double-sided 
insulator ) actually nor a PROTO BOARD card.

I have to learn to do projects in electronics based on the 555.
I am learning the operational amplifier "amplificateur opérationnel" as a converter, inverter,
comparator and amplifier or so. I am a software guy.

What does happen if I create a 25MHz Z80 expansion card for a 2,8MHz Apple//gs ?

Is there a difference between the slots of the Apple//e and the Apple//gs ?
8bits for the Apple//e and 16bits for the Apple//gs.

I think there will be a lot of new hardware projects for the Apple//gs now that you can send
a PCB (Printed Circuit Board) project with internet and receive your board from the post office.
You don't need to have a "insoleuse double face" (double-sided insulator) nowadays.

Sorry if I have disturbed the forum but I am only a software guy with hardware questions... :-)))