My next kick....

So the HTz hopper is supposed to be a copy of the N&W H-11. Does any of our HO manufacturers model an N&W H-11?

Has anyone looked at this as a kitbash?

I made one years back out of one of those Life Like / Bev Bel 100 ton HT's. The rib spacing seemed correct. I just took about a foot and a half off the top and replaced the top plates. Not sure if the slope sheet angles were correct though. RRDavey has it now. Maybe he could post a pic of it.

That is exactly the conversion I am working on. Somewhere in life, I acquired several dozen Life Like hoppers real inexpensively. Some Reading HTg, Some Reading HTd or e, and some CSX/B&O. The plan is to chop the tops off, then slice the top off right below the rivet line and put them back together. The second part of the plan is to reframe them. These are old cars so they have "talgo" trucks with horn hook couplers attached to the trucks. I have a about a dozen McKean 100 ton hoppers. Nicely lettered with Reading speed from the RCT&HS project many moons ago. Of course they are welded cars, not riveted. It was what was available back in the eighties. So I will keep a couple intact for the display shelve (- history?) and the rest - I will pirate the frames. That drops the whole car down - looks better.... I think. The car on the left, chopped down, but the top has not been completed yet. On the right the untouched LL.

Your frame mod does look good. That low slung "rake" is an important modeling feature, even though you usually have to carve out some of the carriage to get wheel clearance. Those LL hoppers are great late-era kitbash cores. I bought up a bunch of them as well, specifically to make HTz's, but then changed my era. As a novice project, I wound up just shaving down the stock bolster pad flush with the frame and sticking the talgo trucks back on, sans the horn hook box. Not real pro, but it tracked pretty good.
Looking forward to your first prototype completion.

they do stand out in a string of conventional hoppers! There was an article with plans in RMC a ways back....Eric Neubauer, I believe...

Granted it has been better than twenty years ago, but I wrote to Con-Cor and aquired several hopper car frames in order to convert the same number of Life-Like cars. The Con-Cor three bay hopper car frame fit just right and the car body now rode at the proper height. Maybe they can still provide such parts and nice service.