Kraig, I checked with my brother regarding the rod situation I referred to, and am told that that the guy must be using a used or refurbished crankshaft which has had the rod journal turned down to a smaller diameter to eliminate imperfections. Thus the rod has to be ordered in the correct "undersize" to match up with the smaller diameter of the crank journal - all of which, of course, echoes what you just mentioned. I thought I was getting a "new" engine..so am still a bit confused. The guy had told me a few weeks ago there was an issue with the rod and that he had to get another one.
Thanks for more thoughts on the JB Weld. I'll still try it. If the tractor basically drives the way it has been that'll be fine. As mentioned previously, I want it primarily to do some mowing in open field areas next to my property. Bought a new tractor this past September but hate to subject it to the rougher terrain and tough weeds, etc. in this other area. If things don't work out well with this 129 engine project, then the whole thing - plus my deck, blade, etc. will all go for sale. Granted I'll never get a fraction of the money back I'm putting into this. I'm also going to be selling the old block, head, plus a few other items. It's ultimately a problem of being too sentimentally attached to the old thing...is the only tractor I've ever owned up until last year.