Brake booster
It actually hist the motor? I would say something is wrong. I have the 11" boster on mine and it's no where near my SBC. With that said, are you sure that your frame mounts are in the right location? there are three sets of holes on the frame for the motor mounts to be located in. I believe that it goes something like this, The forward holes are for the big block, The second set of holes is for small block and the third set of holes if for straight six.
I would check and see if your mounts are right first. The 7" booster is an option for you, it's a dual diapham and it sill work just like the 11" single. Is your booster mounted to the firewall or is there a bracket that moves it out inot the engine compartment? if it's on a bracket and it's not an original instalation then who ever installed it might have put the mounting bracket upside down. With the truck on somewhat level ground the front of your master cylinder should be dipped downward, or should I say should have the front portion lower than the back. It's going to look like it's bent down i the front just slightly. When you fill the master cylinder it's going to have maybe like 1/2" of the reservoir area showing. WOW I didn't explain that well..
I'll try again... Take a glass of water, fill it up to about a 1/2 inch of the top. Now lean the glass over like your going to pour it out but stop and hold it just before any of the water comes out. This is what your master cylinder should loo like when you pull off the cover. fluid level should be ready to run out the front and the back of the reservoir should still have some of the chamber showing... I hope like heck that made sence....
The booster should be close on your BBC but should not hit your motor...
Hope that this gives you some ideas as things to look for.....
