Building an AMT '69 Barracuda model, need some help

It sounds like a great project to do with your son. Testors has the glue too. I haven't done one in ages. I always painted the parts before detaching them. You might need a small paint brush to touch up where the tabs attach afterwards. Don't overuse the plastic glue it can soften parts. Also best to keep paint off of, or scrape it off glue contact points.

Hobby shops, and even Walmart should have the model paint & plastic cement.

Hope that helps a bit.