On my 45 degree adapter, I did have to trim the drip rail about an inch or so, not sure how an e body would be. I had a lot of little fitment issues with my headers, power steering ( borgeson) and starter, that would of been a nightmare if i had the engine in first. BTW, if you are using the MP hellcrate controller kit, make sure all your sensors are from a 2015-2017 engine. Ive seen a few people use a 2018 engine and up, and not change out the sensors and have issues, mainly the MAP sensors, they are different, Good luck.