Can it be done if your Human, Lawfull Good, and all stats high?

I think that with 2nd edition rules, you're only able to play a pure-class Paladin...

No. There is a thread about dual classing on this forum. You can find a complete list of conditions for dual classing there. At this moment, what is preventing you from dualling to a paladin?
Every dual class must be a valid multiclass combination with a minor extension that you can dual from a special kit to a general class (for example, kensai/MAGE). See your manual for valid multiclass combinations. A multiclass "something/paladin" does not exist. Therefore, a dual class "something/PALADIN" does not exist, too.