Drilled out 904 Valve body

I remember installing a few shift kits in the early 80's where I had to drill out this portion. The kit never explained what it did. Just said do it. There were also adjustments that had to be made the the line pressure and throttle valve. Also had to drive in a restrictor in the case.

Since the B&M plate is basically a stock plate with a couple of holes enlarged it should be ok but I can't say for certain. I guess there's only one way to know. Go for it.