Just bought this 86 Suburban. Wondering if I should leave it as original as possible or change some things under the hood. Currently the intake manifold is leaking and it seems like the carb has an issue. Thinking of putting a edelbrock intake and carb since it all has to come off anyway. This burb has all the original smog stuff too and I was thinking of removing it and putting headers on it. I'm told that these changes will add quite a few HP and get better gas mileage. Thoughts? Advice?