I have not tried one of those kits, but here are a couple things to consider. Some aluminum tanks are cast aluminum and pushing/pulling dents out of those can easily crack the tank. If it’s made from formed, stamped or drawn, sheet aluminum; some dents may be able to be taken out, but those kits often rely on being able to get at the back side of the metal with rollers or other pry/push tools for many of the dents, and that may not be possible working through the fuel filler hole, depending on where the dent is.
Dave
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