Install kit questions.

I'm getting ready to pull the trigger on a 6.4 swap on my 74 Swinger. My car currently has a 5.9 Magnum with a complete TTI exhaust on it. What is the differance between the TTI, Holley and the various other swap mounts available. I'm either going with Holley or TTI. I will also use the TKX from either SST or American Power Train. Thanks in advance.