Dan,
The mod I did 30+ years back drew air from NASA duct located below the cockpit that also held the tow hook. Not much flow while on tow because it is blocked by hook and rope, but it was adequate after release. The air went to a 1" hose that could be directed where desired, usually on my face (held by a rubber band around the canopy release knob). Vent air could be directed onto the windscreen by plugging the hose..........not very aerospacy, but it worked well. If you want more vent air you could add a small vent to the aft canopy. Aircraft Spruce & Specialty sells a 3" circular vent that can be popped into the appropriately sized hole cut in the canopy.

N301J was my pride and joy until the "Spring Surprise" of 1982 when I was informed I would not be allowed to fly it in competition any more because it exceeded the manufactures gross weight which was (and still is) 662! Thank you Carl Herold!
Enjoy your new bird,
JJ