looks like a great project. definantley will be in EP.
the stiffening you've done is first class.
to be competitive in EP you should exploit every section of the rules. i.e lexan windows, delete all unneeded parts.
other cars will be as light and likely built for racing too.
considerthe following upgrades:
aggrsive cam, pretty crucial for Prepared
alternative trottle body,
lighten and balance crank, if you've got the tools.
peloquin atb lsd, or clutch plate lsd: essential 2 put the power down.
polyurethane or aluminum engine mounts (black forest industries)
larger slotted/ cross drilled rotors
the 15" sub zeros should fit over larger rotors. and you will have plenty of torque running 225/50/15's.
p.s. keep those hoosiers warm and wrapped up until your ready to use them.
best of luck