It's a neat idea, but the whole point of a Garratt is having the boiler between the trucks allows it to have a bigger diameter and a big firebox. This model looks too skinny to me.
Live steam Garratts have been built in G scale using pairs of chassis from various locos, but no K-27 ones yet...
Would have made no sense for the Rio Grande to do that since they had a wide enough loading gauge on their alignments to just go outside-frame with the K-36 and K-37, ending up with standard gauge boilers on 3-foot gauge axles
