changing tuners on a National Estralita Deluxe Koa

[stefanorini]

Hi everyone, I'm here to ask for advice on changing the tuners on my National Estralita Deluxe Koa (this resonator guitar: http://www.nationalguitars.com/instr...itadeluxe.html). The ones installed by National Guitars are really bad: hard like a stone and nearly impossible to use...too bad for such a lovely guitar.
I am used to the smoothness of waverly tuners on my Martin 000-28vs so I was asking myself: is it possible to buy and mount waverly tuners on the National? Is it easy to do or do I need someone to do it for me in your opinion?
The ones installed now are 3 + 3 in two pieces, like in the pictures on National Guitars' website.
Thank you!