Inorder to correctly reindex the intake cam for the Exintake mod, you have to drill a precision index hole 197.5' clockwise from top dead center.
Since I don't have a machine shop handy, I used my trusty 3d Printer to make a jig to aid drilling the hole.
this Jig can be inserted into the cam gear from the front or the back, and with a drill press will ensure the hole is precisely where it needs to be for the correct timing.
As a test, I first used the Jig from the front position, and made a small drill mark. Then I fipped the work over and inserted the Jig fulliy into the rear of the gear, and drilled using the rear position. I stopped just as the drill was penetrating the work piece to find that the initial center mark was precisely aligned with the hole I was drilling!
insert cam jig into front of cam gear, using the 3 pins to align the jig.
use a 3/16th or 11/64th drill bit to mark the center of the expected exit of the hole. use the hole marked front.
remove the jig and reinstall in the rear of the cam gear. using the same bit, align and drill the hole, go slow, and use oil.
as the main bore breaks the surface, you can check that the predicted center matches the actual bore.
remove the jig, and test fit. at this point the cam should not slip directly onto the gear. the hole will have to be refined with a file or a 13/64ths bit to actually accommodate the alignment pin.
refine the hole by using a larger bit to chamfer the edge on the rear of the gear.