still using old school GEM on pd extended on my side, in parallel with PD-47-64bit pd for sound…
jm
I don't know what OS you're on, but if you install packages on 64-bt linux they will be 64-bit. If you build them from source on a 64-bit machine they will be 64-bit by default.
Although it is rather difficult to build pd-extended because of all its dependencies, it should be possible to make a 64-bit version. There is no explicit use of the -m32 flags in any of its makefiles.