Hello, I am in the process of wiring a MSD ignition in a 67 chevelle SS with a 396. What is the best place to splice in the switched small red wire? I wired it to the pink wire on the ignition switch, but the car does not shut off. Is there a better place to splice in the wire? Also, what is the easiest way to incorporate a toggle switch into this system? Thank you.

Don't have an MSD but I've heard of that problem. Do a search of this forum, MSD shutoff, you'll probably find the answer.

I am familiar with the diode fix to this problem, but i am still wondering where everyone has the small red wire spliced in. Thank you

I am familiar with the diode fix to this problem, but i am still wondering where everyone has the small red wire spliced in. Thank you
I used the original resister wire that went to the coil+ for the points. The small red is only for internal switching and doesn't pull any real current as the big red actually powers the ignition. the small red will "turn on" the box with as little as 4-5 volts so using the original resister wire is not a problem.

Also, what is the easiest way to incorporate a toggle switch into this system?
You can use 2 toggle switchs to really keepum guessing. Put one toggle switch on the small red. See below for the second toggle switch, taken from the MSD 6 series instuctions

THEFT DETERRENT
The MSD provides the opportunity to easily install a theft deterrent kill switch (Figure 4).
White Wire Trigger
When using the WHITE wire to trigger the MSD, install a switch across the magnetic pickup
VIOLET wire to ground. When the VIOLET wire is grounded, the vehicle will crank but not
start.
Magnetic Pickup Trigger
When using the mag pickup to trigger the MSD, install a switch to the WHITE wire and the
other side to ground. When the WHITE wire is grounded, the vehicle will crank but will not
start.
http://www.msdignition.com/pdf/6%20series/6series.pdf