JEFF, HARRY - I'd be more comfortable saying the 72/1X4/73/1X6's were the best gear drives. I actually liked my old 129, the removable center frame section was nice for working on the hydro. Plus I think the frame was stiffer in torsion, it wouldn't twist the frame when you drove up out of a ditch where the frt axle articulated as much as it could and you hung one frt wheel in the air. The NF's twist a bit when you do that. BUT, I know we'll get disagreement from KRAIG about the 125's not being the best CC ever. I almost bought a basket case 125 a few weeks before I bought my basket-case 129, but it needed more work/parts/money than the 129 did.
According to the home page, the 86/1X8/1X9 production started @ 400,001 and Q/L started @ 529,811, or 129,809 tractors. The Double-Zig-Zag grill tractors started with the 72/1X4/1X5 and ended with the 73/1X6/1X7's which is actually what I meant in my post, so from 218,010 to somewhere close to 400,000 is 181,175 tractors with the double zig-zag grills,(Some numbers were evidently skipped, 72/1X4/1X6 stopped @ 306,085 and 73/1X6/1X7 started @ 307,000) but I doubt they built the 73/1X6/1X7's all the way up to 400,000, so maybe they built 140,000 to 150,000, maybe more, of the double-zig-zag grill tractors in total. The only difference between the 72/1X4/1X5 and 73/1X6/1X7 was paint, decals, and the one-piece fenders on the 1X6/1X7's.
So yes, more double-zig-zag CC tractors built than ANY other style of CC. But if you take the 72/1X4/1X5 (88,175) separate from the 73/1X6/1X7's (93,000), Yes, the 86/1X8/1X9's were the highest single series produced. As Bryan told me once, Everybody has had a 129 at one time or another.
Guess what I'm doing is playing the game with CC's like what Gov't Motors/Chevy does with trucks. Ford sells more F-series trucks than either Chevy or GMC, but General Motors with both Checy & GMC sell more trucks than Ford.
And HARRY I have to agree with you about the quick-attach latch, makes installing/removing frt & center mount attachments so much easier. Best attachment hook up on any garden tractor!