I really like imgur for hosting pics, but there are a lot of options. Find a host, and we'll walk you through posting.
Most scratch built bodies seem to start with atleast 0.040" - 0.080" styrene for the initial panels, then either cut in detail, or add thin panels on top. Gusseting corners and internal bracing really help with large flat areas not warping.
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My ALF was my dads built by amf wen-mac, purchased for him new by my grandpa at a Texaco station in 62.
I believe it's in the 1/12 to 1/14 scale range. Some measurements would help determine actual scale. Sorry for the continual hijack, i like fire apparatus...