Bi amping question

Ok, so I have never bi amped. I have always had a dual mono ss b&k. I have recently bought a set of gallo 3.5. They are not bi wired like my old vandersteens, so I am wondering how to amp them.
I was considering having the b&k modified, but I really love tubes so I am leaning towards tubed monos. The problem is cost.
After buying the gallos, I don't have another 3-4k to sink into mono amps. I was considering a jolida 502p or prima Luna prologue 6 monos. Leaning heavily towards the jolida bc at 1k I could buy one now and a second later as They are bridgeable.
But it got me thinking. Without biwireable speakers, can two stereo amps be used? Can you run biwire from the left and right outputs of a stereo amp into a single speaker input such as is found on the gallo?
If this doesn't cause an issue, is there any benefit? Being able to do this would open up the possibility of a whole host of good tube amps that could be purchased one at a time to provide the power and separation I am looking for.
I am sold on monos as I have heard the difference in soundstage and imaging in my system when going from a stereo amp to dual mono.

Thanks. This may be a newbie question but I appreciate everyone's input.

Brad.
Audible illusions modulus pre, Cary cdp, gallo reference, and b&k amp.