What do I need to include with amended return if correcting tuition costs?

My 1098-T from a past tax return is missing some tuition costs so I amended my return for that year to address it which resulted in education credit change. With my amended return what do I need to include? TurboTax indicates that I just need to send the forms it generated however the 1040X says "attach any supporting documents". Do I need to attach the tuition bill and proof of payment in that tax year?