Building a 493 with RPM heads, I need clearance for a bolt holding water pump mounted brackets at front corner of driver side head. Is it safe to grind some clearance on this corner - I mean are there water or oil galleys there?

I ran into the same problem with Edelbrock heads when I was installing my March brackets - I ended up shortening the bolt a bit and using a thin jam nut I bought at Home Depot (or Lowes - I forget which).

Mounting Bouchillon PS and AC brackets, even with a jam nut I'll have to grind a little. Oh well, what could possibly go wrong?

Thanks for the pic.

I had to mill out a decent size pocket in that same spot. No problems in about 5k miles.

i had the same issue and think i changed the bracket to clear. would have been better to grind the head as long as you dont hit anything.
looks like they just got lazy on the ends of those heads and left them square. i never liked the way they looked on the ends when i got my set

Thanks, good to know. The PS bracket has a welded-on nut, then the AC bracket goes behind it - even with cutting the bolt down flush and using a washer and jam nut, have to grind a little pocket for the nut to recess into. Cheers.