that core is just all wrong for the car, I think its upside down?
A greddy kit really doesnt limit ground clearance, if you were to change that 45 degree outlet, welded the other one at the top of the tank where it looks like it was already there judging by that plate welded to the tank and flipped it around it would mimic a greddy.
But regardless I would just sit tight until the VMIC set up is ready to go in, why put anymore time into what's there now?

 

Only issue with those setups is the 9 miles of piping and multiple couplers used to hold it all together.

 

yep, thats the tradeoff. the HKS piping run isn't actually that long, but it does have a couple extra couplers to make it serviceable.