my 91 wrangler has a soft top, and I am currently looking for a hard top. What am I going to need to make the swap? is it a direct fit? what hardware will I need? is this going to be an ordeal?

thank you, 1st jeep, now

Did you try to find them in online auto parts shops.. because i notice that there are lots of stuff which we couldn't find in stores by walking.. and also sometime on very cheap prices... You should try on internet..

The necessary hardware should be included with the hardtop. There are several pieces you will need to remove that are soft top specific. The doors are your big challenge. The soft doors will work with a hard top provided you have the correct style of upper door. One style has a rounded corner. The other has a more squared corner. The corner is the rearward upper part. With the hardtop, you need the rounded corner upper doors. Hard top from any of the YJ years are interchangeable.

Quadratic does carry new hard tops. An Internet search should be able to find more sources.

I have done this swap several times. Always with full size doors.
Many times I found the angle between the front of the door to be slightly different from the windshield angle this can be changed easily to fit the new doors. HOWEVER if the full size doors are already on the Jeep installing a hard top is a simple task. It should just bolt right on there. I have used a roll of thin foam rubber on the side rails before placing the top on the jeep just for a little insurence against dust/water entry.
Make sure to put ALL the bolts in the top as I once had one blow off at high speed.. It was one I purchased on line and was being delivered to me. The trucker said he just kept driving.. I have always thought he sold the top somewhere along the way.. and lied to me about the top blowing off.

As for where to make a purchase.. Look on craigslist in and around your area.. It might take a few weeks to find one but they come available regularly.
Big JIm