I had an issue with birds nesting above my front door. I shouldn't have that problem, I have a 3D printer, darnit!
Print as many of these as you'd like. stacked, they offset 20 degrees.use alternating holes to offset spikes. You can overlap them and secure end to end to make a strip of unlimited length. Use zip ties to hold them together.

(Note: put the zip tie buckle on the spike side, leave tail long, trim to a point. Leave no protuberance unutilized!)

I used a little sanded caulk to secure. but zip ties are an option too