ShopBot with a straight cutting bit and gang the
blocks as much as possible.

http://www.shopbottools.com/

Tom Gardner wrote:

I need the best, cheapest way to cut a 1-1/2" wide by 3/64" deep slot
across a KD Beech block that is 2-1/4" wide. I need to do at least
2,000/day. I already do this but I won't say how as not to influence you.
We are trying to come up with a better, faster cheaper way.