The Eastern Express BA-3 and BA-6 not only don't come without tracks, they don't come with enough wheels
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The kit comes with 11 wheels, ignoring the fact that the vehicles typically had a spare on both sides (i.e there should be 12). The Part PE sets for these kits are a) reasonably cheap - they used to be very cheap, b) spruce the kit up quite nicely and c) include a resin wheel. Part's also probably the cheapest source of tracks - they do a PE set for them that can be had for $16 or so. They look somewhat fiddly, but at least there aren't that many links.
Now if you want a real nightmare with removable tracks, the Aber set for the BT-2/BT-5 is an easy winner...
Hey, Pat, we agreed removable tracks are OK. It's not as if somebody's suggesting a softskin or something
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Oh, speaking of which - not seen it mentioned anywhere here - Cyberhobby's latest "boutique" kit is an armored Jeep, circa 1944. Kit cost is $24.95. Currently in pre-order.
Al