Brian - in my opinion, a mentor is absolutely necessary - I found my mentor at an EAA meeting but it was just blind luck.
A few years ago, I attended an EAA Chapter meeting at Long Beach Ca (I'm not afraid to say where) and was hoping to find someone - anyone, who could advise me about which aircraft kit to purchase, tools, techniques, etc. Sat thru two meetings during which no one cared that I was there or talked to me. It felt pretty strange - I had never been shunned by a group of people before! A new and unusual experience! No tears here ,just the facts, Jack.
So, I went back for some more! During the second meeting that I attended, a guy brought in a rudder and vertical stab under construction for the group to look at. The group tore him apart. I don't know if it was due to poor workmanship or??? I stayed away from the carnage. The guy picked up his emp. parts and immediately left. I have no idea if he was a 'new guy' 'not in the click', or what.
This is where the luck part of this story came in - there were two 'new' guys there and they talked to me. They had the same experience with this group as I. One was just starting an RV-8 with the help of the other. I was invited to 'come and look' any time that they were in the garage and building the 8.
The 8 is now flying. I gained experience just by being there and watching. One of those guys is now helping me build my 12. His help and experience is truly invaluable. I owe him more than I can ever express. He is the reason that I will finish my 12.
So first off, find a mentor - hope that your EAA experience is really good. Don't be afraid to walk away and attend a meeting at a second or third EAA Chapter if you can't find a mentor at the first one or two.
I gather that the KLBG group was/is? only a fly to breakfast group. As far as I could tell, they all flew spam cans - no builders - that's ok, just not for me. No one at the KLBG Chapter was interested in me as a new member. I dropped my EAA membership along with three separate letters to the Director explaining why I dropped out. No reply. Some day, I'll find an EAA chapter here in SoCal whose members are welcoming, inclusive, and builders!