[Thurobred]

I just bought an MSD distributor and i was wondering if there is anything important i should know when swapping the OEM for the MSD? I don't wanna be off a tooth or anything. Do I mark it in any way before I pull it?

[97stang3.8]

i've never done it but i think you just put the number one cylinder at top dead center and set the distributor to fire cylinder one and drop it in without turning it. hopefully if i'm wrong someone corrects me but that's how i understand it to work.

[EagleAutosports]

You don't necessarily have to put the engine to #1 TDC and line it up with the #1 plug tower, you do that when you don't know where it is in relation to the timing. That will work but it's adding unnecessary work. It shouldn't take 5 minutes to swap distributors, then you would set the timing once it's running.
Just pull the stocker out and put the MSD in, making note of the position of the distributor when looking from above. Slowly pull the stocker out, watching where the rotor was pointing to. Put in the MSD to the same position.

If you've never installed an MSD distributor before, know they're built to tighter tolerances so it might need to persuading to work it into the block. It can be very tight.