Base coat olive-grun, with dunkelgelb and/or rotbraun disruptive pattern is a good starting point.

Base coat means the factory finish. All major external parts (including wheels, sprockets, etc) are factory painted. Late war orders were to switch to olive-grun base. Although since this is what-if, bordering on fantasy, you could use any color(s) you wish.

Nick G.:

For whatever little any of this could be worth, given as the E-25 was indeed proposed and possibly partially-built as a prototype at war's end, and conceivably could have gone into some limited production sometime in 1946 if conditions permitted...

It seems that Olive-grun had become the new regulation AFV base-coat in 9145 - and may have continued in effect into '46, so seems a likely starting place. But consider that paint shortages may well have simply become more marked over time even had the Reich continued to fight into '46... So I imagine that hulls may have left the assembly plants wearing OG only on upper surfaces, and perhaps rot-oxide primer on lowers... And factory camo schemes may well have gone away, as they simply take up time, and delay getting vehicles into action.

Recall that the Germans had a long-established pattern of field and crew-applied camo (back to 1934 and the Bundfarben-Anstrict schemes of the late Reichswehr days)... And I think it quite plausible that "Panzer-46" stuff would have likely continued / reverted to that pattern... And unit and crew-applied camo could well have reflected all manner of imagination, ego and emotion, sporadic and localized command decisions, unit pride, etc... As indeed it did from 1941 through May '45.

So... available green, brown, dunkelgelb paints may well have been individualistically used by units and crew - resulting in a range of vehicle schemes - from no added colors (so OG uppers or maybe entire hulls w/ OG solid wheels) to virtually any combo of rot-oxide lowers, maybe RO wheels, maybe one camo colour in spots, stripes, lines, to complex and more-complete tri- and 4-colour camo on uppers. Some wheels may have received a solid camo colour - so a mix of coloured wheels seems reasonable. A really camo-minded crew may have diligently and comprehensively done up their steed, with patterns onto wheels, etc. A harried,crew may have simply slopped one color onto some surfaces and called "done!" with it.

Frankly, the options seem open and wide, Nick! I have one of these E-25 kits, and am thinking of doing it with a "urban-area nachtjager" scheme done in greys, black, and maybe dark brown with some angularity to reflect "buildings and rubble". But hey! Probably any scheme could be "right" for this bird!

Model on and have fun with it! Bob