a/b/y buffers, transformers....can't i just do this?

[boog]

i finally have my dual amp setup (randall full, marshall half) and that's awesome. naturally, i want an a/b/y switch and being a (poor) diy-er i want to build it rather than fork out the cash for a morley. i've done a boatload of reading the past few days and understand (mostly via r.g.) that my impedance get's 'halved' without an input buffer and i get gnarly ground hum without isolation transformers. now come the questions:

is there a way i can create a similar output isolation by doing output buffers? i don't have any transformers handy, and if i did i'm really not too sure how to go about powering the a/b/y schematic on r.g.'s site.

on second thought: i run through an skb45 pedalboard which has dual outputs. it says that they're isolated. i have a buffered pedal (trusty tu-2) at the beginning of my chain. in theory couldn't i insert a passive switch between the final pedal and the input/return on the boards control box and accomplish the same thing as r.g.'s a/b/y on geofex; the buffer supplied by the boss and the isolation by the board? i'd go ahead and try it, but my workshop (also known as 'home') is 45 minutes from the rehearsal space (which is where the gear is).

currently i don't intend on dragging two amps around to shows, but i would like something practical for rehearsal/writing sessions.