I called down to the case IH dealer here in town and they had the buffer spring in stock, as well as the answer to the elongated hole. I right it was odd that there was that much lateral play in the throttle linkage arm. I looked at the diagram and it showed a washer and nut on the inside so I figured no sweat, I'll pop this thing off tighten the nut and we'll be set. Well no dice because the threads only go so far and it was as right as it could go. SO. when I go to pick up my spring from the dealer I bring it along and he informs me of an oil seal that goes on the throttle linkage arm shaft outside the housing, and when that is installed there is just the right amount of shaft going through the housing to put your arm on the keyed part and tighten it down with a washer and nut. It all fit perfect. Now I weight this because I have read as much as I can about rebuilding these and I have never heard of these seals. But I often hear about a sloppy throttle arm. Don't know if this might help someone else or not.
Put it all together, and it worked great.