I'm going to buy a custom throttle cable for my mpi swap from jeggs. should I get the 24" or 36" they have an option for a 48" also.

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I'm curious how the throttle cable connects to the gas pedal. I haven't crawled my fat self under the dash yet and would like to know what I'm up against when I get there. I've searched the gallery and google with no results. I'm going with a different induction setup and need to shorten mine by about 10" and need to retain the ball end on the throttle body side. I was wondering if I can shorten it or have to buy a generic one.