I'll just venture a couple guess, a couple opinions, and take your comments off the air.....

3 issues, 2 combined into the third.

1-Not much clearance for fenders, more on the '85 than any Ironman if that one. The front fender has a good chance of hitting the downtube when turned. There is almost no clearance for the back wheel, and that's with 700x23's.

2-Not much clearance for tires. 700x25's, no problem, but you'll see a lot of debris on the back of the fork and both the brake bridge and seat tube. 700x27's, you'll run in a high-speed corner, and 700x28's, you'll rub if you lean the bike over. The flex of the wheel produces enough movement, under load, to put a 700x28 into rub mode.

3-If you get fenders big enough to put 700x25's or 700x27's under, I can't see how you'll have much space. If you run the clearance that tiight, ride in clean areas, or you'll have a lot of junk under the fienders.

Not to say it can't be done. The rear fender can be trimmed to stop when it approaches the seat tube. The front fender can be shaved in back or just avoid turning sharply. In my opinion, the fork is the issue on the front, the seat tube on the back.

My recommendation is to find a Lemans or Lemans RS frame in the same size. You will get a little relaxed geometry, the extra half inch or more of clearance you need, and eyelets for fenders. I'm building a light tourer right now on one of those frames, and the 700x25's will fit just fine under the fenders. Probably not a snow/ice bike, and I haven't tried cyclocross tires or anything the size of 700x28's.

Good luck. It would be a unique Ironman. There is a guy in CA who built an upright commuter with an Ironman frame, but he didn't use fenders.

As far as a rack goes, I've used a Trek clamp-on rack with excellent results, and it's very convenient.