Not my best work, but I got the grill blocked this weekend! Black coroplast and zip ties, price of mod: $0.00USD!
First test was this morning. Ambient temp 46f, intake temp after warm-up 150f! Yikes!! I had to adjust the cable for the first time. I got it at a steady 130 after a little fiddlin'.
MPGs look good on first stint, 60.5 on my 35 mile commute with a 55mph average speed. normally I see 51-58 depending on wind and temps. I’m pretty happy so far!
Next: Make the grill block adjustable and add a fan-on indicator.