Thanks for all the advice here. I went to the Thai immigration office today with all the documents I had already prepared.
They accepted everything as is. No mention of any proof of funds from abroad. Fingers crossed that I will get my visa.
The only issue they had was with the remaining days on my visa exempt entry. The officer wanted there to be at least 21 days left on my permission to stay.
They allowed me to extend and apply for the visa today.