A "What if" from real life. The Z-37TM was a one-off prototype to test the Z-37T for suitability for military work.
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This, but on floats! 
Have heard some not so pleasing things about the KP Z-37s, but much good about Eduard's effort. So may get both and nick the engine section and winglets from the KP kit and put them on an Eduard Bumblebee.
Yes, the KP kits aren't grand. They had the feel of having been rushed onto the market (to beat Eduard's kit presumably). The most obvious oversight was that they didn't mold the cockpit canopy to capture the prominent buldged side windows of the real thing. They also cut corners in other ways, but the visibility of it depends on the kit and the version it represents.
I'm not sure I'd trust KP kits to be accurate in scale either, their recent 1/72 Cessna 180 kit has come in for a fair amount of criticism for being underscale.
If you wanted to turn Eduard's Z-37 into a Z-37T (hoping it and the KP kit match up in scale and proportions) you'll definitely need the turbo nose and winglets. You'll also need the tail fin as the Z-37T has a very prominent extension of the fin leading edge.
There is also some sort of fairing on the top of the Z-37T cockpit canopy that is absent on other variants.
I have read in some places that the Z-37T has a longer wingspan than the Z-37A, but I can't find anything that says if that's just down to the winglets or if there's more to it.
I'm also told that the rear fuselage got some sort of extension when the Z-37T was designed, but I can't find any information to confirm that.
As for floats, I don't know if you've seen this page, but there are a few images of a Z-37A on floats that may inspire you:
https://www.letadlanaplatne.cz/en/film-planes/civilian-aircraft/agricultural-machinery/zlin-z-37-bumblebee/
