Flex plate bolts witness marks on torque converter

I can't see the sense of doing it the hard way. The bushing reduces the size of the crank pilot hole, and allows the use of a stock converter. There is no down side. Why spend a bunch of money on a special converter, when a low dollar bushing will accomplish the same thing. Granted if you want a "special" stall speed converter, then have it made with the big pilot.
I have several different converters, for different applications.
Large pilot-large spline
small pilot-small spline
small pilot-large spline
I can do any combination of engine -904 trans except lock up.
early engine with any non lockup 904
Late engine with or without bushing
early 904 with small spline, or converted to large spline.
PS: I am told that the small spline part inside the converter is getting hard to buy.
The ideal way to do the late engine conversion is to use a late transmission to go with the engine. Larger stronger input shaft, more clutches. However some people have 65 and older cable shifted trans, and want to keep them (push button or factory floor shifter). These people have two options.
1) Early trans/converter, with the bushing
2) early trans with the later front parts in the trans (Low gear set will not work), and the later style converter (no bushing)