I HAVE FOUND ignition modules for 502 EFI's CHEAP!
 

Just thought I would put this out here.....

After searching for an igniton module for my EST distributor in a 502 EFI and seeing that they are selling any where from
$148.00 to $180.00 and not trusting an automotive one for marine use..... I found A direct Mercrusier part #811637T
FOR $39.76 on Amazon.

part #'s that fall in line with this are:
10482830
16139399
D1965A

You found a merc part CHEAPER than the automotive equiv.???? Did you feel that man?? The earth just shifted on its freaking axis. Im literally in shock!