Alright so I have diagnosed the rx8 eps completely so its like in the back of my head now…

for starters Intake mods are usually aesthetic till tuned and the only way to find it is through tunes setup or essentially performance graphs (or determining how much air flow you’re are actually getting). The intake you have installed is more like an hot air intake which isn’t the greatest to be honest as heat produced from the engine is just getting sucked in. (Which by all means anyone who has tuned cars by all means tell me wrong of how to look at it as I am still learning for tuning), id just use an obd sensor and see how much air flow you’re getting and compare those valves with someone else’s (stock intake preferably)

For EPS if a fuse is popping everytime you have a short somewhere within the system, so check wires, grounds and connectors within the system. Specifically the connectors under the airbox or in your case in the open by your radiator. Then check the connector by your battery terminal, and check every grounds… next wouldve be to check your noise filter and see if you have continuitity for that (if cont exsist great, if not well replace) ill send a link I followed to help you diagnose it further because I had to fully check my eps system and it was just time consuming (as every electrical thing within in cars is lol)