Intake manifold bolt removal help

[drewbert41]

Hey guys,

I am getting ready to pull my intake. I have everything off and I was able to break all of the bolts loose besides the ones under the carb. I have the carb off and I read that you cannot remove these with a ratchet.

I used an open end 9\16 wrench and the bolts seem too fat for me to turn the wrench. Cant get the box end side on all the way. Don't want to round these off. I have a 1974 350 in it with the emissions crap and there is not a lot of room to turn it.

I have scraped around the bolts to clean it up and vacuumed debris.

Searched the web can't find much. I hear people silicone these in place.

Am I using the right tool for the job? Should I buy an offset box end 9\16 wrench?

Is heat or penetrating oil a no-no?