340/904 flex plate
As long as the converter bolt circle and balance are correct, they work.
I use the one that says it's for a 727/360 combo on a 360/904 so go figure.
Look at 10231, it says it works for both 904 and 727, what's that suggest? It's the same flexplate design as the 10230 except with 8 bolt crank attachment instead of 6 bolts.
Call B&M and ask them. They no longer make the 10235.
Good luck