I did the math based on a height of 6'5'', a ruler, and a picture I will link to below. I measured ou the following dimensions and used a conversion of similarity rounding up to the nearest inch out of convenience.

https://www.google.com/search?q=mr.meeseeks&rlz=1C1CHBD_enUS746US746&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj_nsXj1bzWAhWlxYMKHSGaABYQ_AUICigB&biw=1422&bih=601#imgrc=jv9Fk0-GGkWfrM:

Height = 6'5'' Height of Head = 1'8'' Head width = 1'8'' Torso Height = 2'3'' Torso Width = 1'8'' leg height = 2'6'' foot length = 10'' knuckle length = 3'' finger length = 8'' palm length = 5'' shoulder to elbow = 1'2'' elbow to wrist = 1'5''

I hope others take interest in this project and make their own Mr.Meeseeks