Go for it. Can't find any photos, but I took a pair of the little Wms "027"-PW-clone Erie FA2's and swapped a power truck from the powered unit to the dummy. Installed ERR Cruise Commander, Alco sound and E'couplers, directional headlights. No smoke. Used a tether, of course. They are arguably the smoothest-running locos that I have, and not a dummy between them.
They will creep.
I use them as a switcher. The official story is that they were small meter-gauge streamlined Alco S-4's for export to an Unnamed Balkan Country, and the deal fell through. Kind of a Russian Decapod situation. So Alco re-gauged them to Standard, replaced the buffers with knuckles and sold them to US railroads. That's my story and I'm sticking to it.
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3/20: Found the photos:
My "tether" is actually permanent. I didn't have one that was workable at the time, so I just hard-wired it. Not a problem with these small FA's - I just handle them as one unit, kind of like an articulated. I haven't had any need to fix anything in them, ever. All you would meed to do is remove the body, anyway. But, a tether would be better.
Note the homemade drawbar rather than a pair of couplers. Choose your separation. They could even be closer.
