NACCA ducts could work, installed backwards for natural suction. With no inner fenders and the firewall moved back as I have it, ducting to font edge of the door (vertical point between the hinges) and capped to make the vents functional shouldn't be too bad. The firewall is about level with the door hinge pillar. Or cut the whole bottom of the fender off level with the top of the tire like 80-90's IMSA cars. The header exit will likely be there also.