Thanks, everyone! I really appreciate the feedback. I bought it in the late 80's boarded and bagged with the flap taped, which is how it stayed for the last 30 or so years, until I opened it yesterday to move it to a new bag with a new board. I recently reacquired what remains of my comic collection from childhood and am trying to decide how best to go about preservation and what makes sense from the standpoint of the value of the books. The TMNT No. 1 is far and away the most valuable. The other stuff not so much, such as TMNT No. 2 (first print), first print Dark Knights, DD #158, etc.
I think I may send in the TMNT Nos. 1 and 2 for grading (maybe pressing).
Happy Memorial Day!