Well if it hasn't been running last since 2001, then yeah, it may be old gas and it may also be that the old gas in the carb could have varnished over and be clogging who knows what inside the carburetor. It's probably safe to say that if it's been sitting for a while you may need to rebuild that carb and give it a good cleaning. Stalling up an incline sometimes can mean float level problems. That's a common occurence on some cars that may stall when going around a corner too fast. The float level is not right. Believe me, right out of the box my float level was WAAAAY off and had I not fixed it the car never would have ran right. You can find the flaot adjustment setting and "how-to" on Edelbrock's website in PDF form. Defenitely flush out that old gas, add a new fuel filter,(and consider new lines eventually) and check the float levels and inside of the carb for any leaks or gunk build up. And while you're at it, check ALL your vacuum lines. If they are rotted and causing leaks, it may also complicate things. Check those and report back! Good luck

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