JPCycyle, and others sell kits to do this. It includes the triple trees, spacers, front brake rotor spacer & hardware and fender mounting spacers & hardware. I did it to my 1995 Dyna.
My kit was about $550, but others are more depending on materials like billet aluminum. Mine's chromed steel. You'll also need a new lower bearing and dust seal for your steering neck. Not worth trying to get the old one off and not damaging it.
Keep in mind too, you have to order a kit for am internal steering lock and not external.
I added a 21" front wideglide wheel/tire, and a factory matching wideglide front fender to eliminate the fender mounting spacers. Most people think the bike is a Wideglide, unless they notice the 39mm front forks, rather then the 41mm ones.
I also changed my headlight to the Bates, from the brow-type, and remounted the guages off the bars.