Changing the Spec Racer Ford air filter is very simple requiring no tools, just a simple rag and possibly some degreaser. Most people change it just before qualifying or if it is soaked in oil due to engine blow by.
Equipment & Tools:
New Air Filter - Enterprise PN: 592231 / 592231F / Fram CA 3660
Simple green or your favorite degreaser
SRF Gen2 Air Filter Replacement
Remove the old air filter by unclipping the two upper and two lower latches on the air box. The air filter should just pull out easily.
Inspect the inside of the air box for oil or debris and clean out with a rag and degreaser if needed. If you have oil in the air box it might indicate excessive oil blow by and potentially a tired engine.
Insert the new filter into the air box.
Latch the two upper clips.
Latch the two lower clips and you are good to go for the next session. Hopefully the engine breathes a little easier and maybe gives you more tenths of horsepower but I doubt you will notice it on the butt dyno.