Crazy, with the MSD, if the box is a 6 series or larger, then there are two ways to connect the box to the distributor pickup/module.
In your MSD kit, there is a pigtail lead with a black plug and two female terminals on the other end of the wires, one is for a larger male terminal than the other. This pigtail connects the HEI pickup directly to the MSD magnetic tgrigger wire plug or extension lead from the MSD box, and bypasses the HEI module. The large terminal goes to the pickup white wire, and the small terminal goes to the green wire, then is routed out of the distributor body to the MSD unit or extension mag trigger wire plug.
The other way to trigger the MSD box through the HEI is to connect the white point wire feed from the MSD to the "C" terminal on the hei module (the letters are clearly marked on the HEI module on the top of it), and the MSD will read the signal as it does for a popint system. Works the same as the magnetic trigger sensor described in the above paragraph.
Always, the magnetic trigger input is better and more stable for the hook-up than the HEI module/white wire is.
BTW, with the MSD, don't leave the tachometer feed lead on the coil negative terminal, it now goes on a male stud on the MSD box end, and if your tach won't work that way (most stock and aftermarket tachs work fine there), then a tach adapter is available from MSD to make it work right. Instructions for this are in the install sheets, including a list of tachs and whether they need the adapter.
I don't get anywhere near the Crane ignition proiducts, but I will tell you which wire is the positive and negative outputs from the HEI pickup. The white wire from the pickup is the mag plus (+) feed wire, the green wire is the mag negative (-) feed wire, and they should be connected to the Crane magnetic feed wires as such. Reversal of the polarity and wires will mis-time the engine about 45 to 50 degrees, so get 'em on right. You will find the proper wire polarity for the Crane units listed in their installation instructions.
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