^ there is a small filter inside the block under the oil sending unit. Unscrews the oil sending unit from the block and you will see the filter, you should replace the oil sending unit as well but you dnt have to cuz the filter is what's more important. If you dnt you could see oil pressure drop while the engine is at idle and possibly at high RPM, this is a small but critical part that is often overlooked. Just food for thought I'm Certified GM Tech and Corvette Certified, I rebuild and over haul Engines, Transmissions, and Rear ends all day everyday.

That's gonna be one badass motor when your done, I just built an engine in our owners corvette with the same parts minus that intake. That's one nasty cam your getting and will have a nice sound, good luck with the build.