I worked a little but mostly kicking back. Lost a box full of 6203's about 110 of them in the box and I can't find it in my shop. Last time I had them in my hands I said I will put them someplace so I can find them easy but so far it hasn't been very easy
My limited Lester says "The 17786 is a later Version of the 17564, probably using a Later Ignition Switch Terminal on the Solenoid", but you probably know that much already.