What options for O/D behind a S/6?

We are anxious awaiting delivery of my daughter's (first car) '62 Valiant Signet 2dr H/T. We have a good 225 coming with it, ready for install.

I plan on installing an A500 in my '67 'cuda, but am curious what options there are to put O/D behind her S/6. I actually have an aluminum case 4 spd O/D from a low miles Feather Duster, but she REALLY wants to keep the push button shifter. I'm aware that Imperial Services makes an adapter cable set to connect button shifters to newer lever style transmissions.

Any ideas? I'm not above having an A500 forward case machined down and doing something like the UltraBell conversion to put an A518 behind a big block. I was thinking of using a S/6 bellhousing and custom adapter plate.

Thnx, Mike in FL