Can I run 2 trailing igniter's to run 4 trailing coils with this ecu? Or do I NEED 4 leading igniter's?, what is everyone else running?

 

You would need 4 ignitors. Stock FC coils work well to 400-450 whp in my experience. Over that the easy button solution is 4 x IGN-1A.

 

We did 645 on a mustang dyno with 4 leading turboII ignitors and 4 trailing coils. Reason we did not go further was we ran out of fuel. E85

 

i have not personally tried it, but you could run this as ignitor with FC coils..
QuadSpark Four Channel Ignition Module DIYAutoTune.com
it peaks at 11.5 amps, a bit of an upgrade from FC ignitors which can only do 7-8 amps

you can also find a 4-channel ignitor on some vw/audi cars:
Bosch 0 227 100 211 Ignition Control with MegaSquirt-II
that will do up to 10 amps

 

To run 4 stock coils, 4 leading igniters... settings should be
ignition = mazda 24 and 2
trigger = direct fire

correct? or what other settings should be done?
I wired the coils like the rx8 shows in the book...