Hi there!
That's a lot of questions, so here goes.
The main difference between the L and the L1 is avionics. There were 5 versions of the L1, all were progressively more complex and capable avionics fits. Mechanically, they are there of there abouts the same.
The L/L1 is the stretched version of the 332 C.
The Autopilot is a standard fit.
I am not 100% sure, but I think that the Flight director does come as part and parcel of the auto pilot, one of the other guys might be able to confirm.
I hope that helps