Hi Po Exhaust manifolds 383-400

I appreciate any and all input. I bought this car really cheap- I paid less for the entire car than the guy had in the engine alone. He did a lot of work to it and basically the enitire under carriage and drive train is brand new with 4 wheel disc brakes. I'm wanting to build a cruiser and not a racer per se. I'm adding a March Performance complete serpentine system and a Vintage Air set up as well. From the dyno numbers the previous owner showed me I should still be north of 500HP even with somewhat restricted exhaust and the add ons. Hopefully anyways! I hate having to collapse header tubes to clear everything. I have been eyeballing the TTI's but not sure how low they sit. the car is dropped a tad in the front.

Again, thanks for any ideas any one has!