George: I noticed the height difference the first time I bought 1015s. Considering that my cars probably vary by at least 0.005 inches, and the prototype can vary more than that between empty and fully loaded, I consider them interchangeable. If one is too high/low, the other one is too.
The 1015 and 1025 mounting holes are also the same distance from the end, so I use whatever I have that clears the bolster. New non-MT cars are getting 1015s because they're cheaper in bulk packs, while converted MT cars usually get 1025s recycled form the trucks. 500 pair of draft gear boxes and lids will go a long ways. I'm surprised MT doesn't package and sell them for people who want body mounted couplers. I special ordered mine two years ago.
Bryan: I probably will buy the trucks. Filing a hundred or so boxcars was bad enough, but there all I had to do was file the bolster flush with the center sill. On the tank car it looks like the bolster has to be higher than the bottom of the center sill, which will require much more care in filing, and being plastic, it will be very easy to remove too much. Besides, it will give me a chance to try the BLMA trucks as replacements. So far the only ones I have are on their cars.
As for the holes, I tried drilling new ones, and it did work. All five cars are drilled and tapped with no breakage. I don't know how durable they will be, but since I don't run 100+ car trains, it shouldn't be a problem. I never thought of using 1016s, and I do have a few in the junk box, since they used to package both shanks in a package for locomotives, and I used the 1015 on all of mine.
My latest 1015s already have the box countersunk for flathead screws, although MT still includes their standard screws. I have four gross of 3/16 inch flatheads on order from J I Morris.
