Any tips for picking the best fit technical cofounder? | i will not promote

I’m leading a VERY early stage startup as a business founder and am actively interviewing potential technical cofounders. I feel incredibly lucky that after only a month of asking around, I’ve gotten high-quality referrals who are seriously interested in building with me. The issue is that I think current candidates would make great first eng hires, but technical cofounder would be a stretch for them. They have great technical chops, but haven’t worked in startups and I get the strong impression that bootstrapping and deviating from the traditional SaaS playbook would be an adjustment for them. Since I do intend to split equity evenly, I want to be really, really sure that I make the right choice and everyone is positioned to be happy. I have an inkling that the very best fit person for the technical cofounder role is not someone I know personally. Any guidance on recruiting someone great who might be outside of my network?