Shad is great. It is also my number one halibut bait. Unfortunately, It gets a little expensive, my being so far from shad water up here in Blaine. When I used it in California back in the dark ages, I did the same thing with it. I did not cut open the body until I was ready to crab. I then partly fileted it. It kept things so much neater. I have never used roadkill, but then again why would I when I can use a couple of nice clean fresh bullheads rapped in a ziplock bag. No mess, no smell and no fuss. I almost always limit including culling in one or two 30 minute delay pulls. Note: I always clip off the staghorn spikes as soon as I catch a bullhead. It makes them harmless to me and the ziplock. I bought a stainless wire cutters just for that purpose. That is another trick I learned for catfish back in the dark ages.