I have made a few 2 in 1 picks as per snapcarp's excellent guide elsewhere on this site, but the other day I bought at a car boot sale a large steel lever padlock with no key. Granted it's got only 2 levers, but it took me a while to pick with wires as (a) I'm not very skilled with them and (b) the keyway has a central post, making it more tricky to get them in.
So...I adapted snapcarp's design and made a hollow 2 in 1 but it's only hollow for the end 2cm or so. The rest has a solid core to maintain structural strength. It works like a charm. Now to purchase a 5 lever padlock for a real challenge...
If any of you wants to make something similar but can't tell from the pic what to do, fire me a pm
Magic