Charles, I bought 14 AWG teflon tubing from PartsConnexion to go over the leads and it is a good fit. 16 AWG could also work (I bought both 14 and 16 just in case) but would be very difficult to work with if the leads are long (tight). Personally I try to avoid cutting the leads too short in case I want to remove and reuse in another application or to sell.
Oeaohoo, thanks for the info on the CAST with Almarro. I just ordered a pair of 0.1uF. :) I haven't heard any Bel Canto DACs older than the 3, but the Havana is a warm, organic sounding DAC. Very musical with the best tone and texture I've heard in my system. In its stock form it is not as detailed or transparent as some more expensive DACs, but with parts swaps -- especially output caps for CAST -- performance is raised several fold. I haven't heard a DAC in my system that I like more including Calyx 24/192, Metrum Octave, Bel Canto DAC2.5/3, Berkeley Alpha 1/2, PS Audio PWD Mk2. There is a huge thread on Head Fi if you want to learn more about the mods.