Hey all, i am in the process of building my second Ziroli Panther and i wanted to use the wing plug ins that are available on most yellow kits. The narrow aluminum spar, and spar retainer. Where can i get these, and also, do you think it would be structurally strong enough. Ziroli calls for aluminum wing tubes, on the plans. I used them last time, but did not generally like the retention design he has on the plans. Thanks in advance, Nick

Oh one more thing, can i get the spars in a longer length as my wings are bigger than yellows.