I got a Spacewalker 2 from a friend who passed away. I can't figure out who makes it. I think it may be a Sig Kit but not sure

Been reading about CG calculator. But I'm scared of getting it wrong.

its got a very simple rectangle wing.

Its 13.5 in wide and 82in long.

I know. CG is 25-30% of the with

so I'm I right in thinking my CG is 3.5-4in?

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