WhitehouseFilms

Question: Am I doing this correctly?

Recently fitted this Tri-ang Princess chassis with new wheels from Markits. However it appears to be shorting out. One side is plain while the other is insulated just like the original set up. There are PECO fibre washers on all the axles, though I'm wondering if it's the crank pins or the valve gear that's causing the short. 

I'm still trying to learn my way around of converting older Triang loco stock to work with Markits wheel sets and with very little clear guidance or videos on the correct procedure on doing this, I have to try and solve this myself. 

Would someone inform me if I'm doing this conversion correctly or is there there supposed to be a different approach with this?