SFI flex plate Question

my new combo will be an internally balanced 360 based 410 stroker built for boost. I'll be running a Cope built 904.

Can someone recommend an SFI flex plate for internal balance, 6 bolt crank, and 904?

I've looked at B&M 10230 but it is for 727 converter. The 10231 says it will work for either 727 or 904 but it's for an 8 bolt crank.

What have you guys used with this combo?