John,
Use the bulkhead as the peddle stop by adjusting the throttle cable extension so the carb or throttle body is all the way open at the peddles touching point. You no longer need the factory peddle stop. I will assume the spacer kit came with a cable extension provision or instructions to modify the bracket on the center tunnel. Either way it is not a problem unless your foot pressure is so great it breaks the gas peddle arm. They mostly break from not having any lube over time, seize on the pin and boom, it's over. The factory stop will flex a bit where the bulkhead will not so make sure you do not stomp the throttle to hard.
Here is a picture of my solution to the cable extension needed which keeps the factory cable bracket in the original location on the center tunnel.
Hope this helps.
Kirk
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