Bringing this back to the top. I "BELIEVE" I have this figured out so it will actually work. I clamped the idler gear TIGHT against the crank and cam gears with a ratchet strap and printer paper between the cam and idler gear and between the crank and idler gear to set clearance. I got a 5/16 ID, 3/8 OD reducer sleeve and pressed into the 3/8 bore I had drilled through the center of the idler gear pinion and drilled a 5/16 hole right through the front of the block. Then I took the ratchet strap and idler gear off and tapped the hole to 3/8. Now the idler is bolted rigidly in place and it has I would "guess" about .006" of play back and forth for the idler. Should be just right. The bolt even goes through the block far enough to put a nut on the back side and secure it even more. I figure on final assembly (a ways off yet) I'll put blue locktite on the bolt threads into the block and on the nut on the back side as well. A good, grade 8 bolt should hold it fine I think. I feel confident enough that this may work. Now all I need is to have the camshaft drilled for the three bolt big block pattern and I'm done.
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