Hi

The Leo 2a6 tracks will not fit as they are a couple of mm wider and have different sized end connectors which mean the sprockets do not engage properly. I have one of these old leopards and am planning a set of the metal tracks when funds allow but in the meantime I use a set (and a half) of the HL Pershing tracks as they are pretty much the same and very robust. The HL ones can be picked up pretty cheaply lots of places.

cheers
Gorehound