personally i would paint them, i have cosmetic scoops that i might convert into functional, ram-air intake. As for the tach. if it works good, if it doesn't pitch it. Just my 2 cents...

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2000 Ranger xlt - 4x4 off road package, K&N intake, flowmaster 40 series, cranked torsion bars, autometer dual pillar pod w/ gauges. Who knows what's next...sold and replaced with 99 Jeep Wrangler 4.0