A few days ago I decided to try and convert this to EM gauge using the existing Dapol wheels.
I would not recommend trying this.
The Dapol wheels are on plain axles with no splines, so standard EMGS 2mm axles 22.2mm long can be used.
Only a fraction needed to be filed off the side of the splashers, strangely on one side only, to ensure the wheels ran freely.
So fairly straightforward.
The predictable problem is that clearance behind the crossheads is nonexistent, not helped by the crossheads being floppy plastic so there is erratic fouling.
I think the only easy solution to this is to wait for someone to produce authentic finescale wheels.
For example, if Alan Gibson produced them the wheels would give 0.4mm extra clearance each side.
And if inverted AG crankpin nuts can be used, another 0.3mm each side compared to the Dapol pin.
My advice is to wait……..