I've picked up a few of those dri-weave athletic shirts on sale. They really work and are great for yard work. Moisture quickly evaporates off them, and they are thinner than cotton, so any breezes are more refreshing.
Yeah black absorbs light and gets hotter quicker but radiates much faster, white takes longer to cool down. So paint your block white and then insulate in white heat wrap :-). And then replace you bearings every 3k miles as you cook them.