Is it best to attach the swivel directly to the spoon or tie it to the top of the leader and tie the leader directly to the spoon? I was wondering if you attach it directly to the spoon if it might impair the action. What do yall think?

I use a split ring and barrel swivel, doesn't seem to bother the fish any.

I've used swivels and have not noticed a difference in fish catching

I use a swivel at the end of the main line, to both eliminate line twist, and provide a reliable way to change from braid or mono to fluorocarbon leader.

I put a split ring on the spoon and attach the Barrel swivel to it. I do it this way because I've bought several spoons that come that way out of the box. I don't really use leaders in fresh water and simply tie my line directly to the particular bait.

Swivels work just fine

I like coast locks size 5, 7? Helps with line twist when you are Fishing BIG Flutter Spoons and Slab Spoons. N. TX Lakes are not clear enough for Striper to see them? Maybe some AR lakes?

http://www.basspro.com/Rosco-Barrel-Swivels-and-Coastlock-Snaps/product/15174/

A number 5 is what ya find on most A-Rigs

On wobbling spoons I attach a split ring and swivel directly to the spoon. With jigging spoons I switch the treble hook to a single and I use a length of stiff fluorocarbon leader, with the swivel 10" - 12" away from the lure. I've found that I get fouled less often that way.