Installing a new motor and was bolting up the trans and saw that there is a 'green' bolt that needs to be installed first? I did no use that one first, do I need to redo it all? Why is it to be installed first??

2000 4runner 4x4 auto 3.4 liter..

 

Recently replaced my converter on my 2000 runner ltd with California tranny. I didn't have a green bolt. I did, however, see that the new torque converter required me to shorten the mounting bolts by a few threads to prevent dimpling to the converter housing. I don't see a reason to mount one bolt first. Just the usual PITA hand tight, then snug, then torque sequence.