Hi Brian, just went through that sort of thing last summer. Just get some square stock (like trailer hitch size), weld up a cradle for the "K" frame. Put some casters on it, then make up a flat stock metal with an adjuster length of square stock welded on it (to attach to the area of the trans cross member). At the bottom weld a caster so the trans will role with the engine. To take the whole thing out as an assembly (eng, trans, "K" member,
and suspension)just unbolt the four main "K" member to frame bolts and lift the car off. Let me know if you need help.
Mike

The wood thing looks good too.