I had to make this tank for my 70 mm reel which holds 15 feet which is still a lot.
I just cut up a JOBO basically and stuck it in a pot lid. However 75 feet is a lot, are you able to Mayne skip frames and measure out 3 feet lengths to cut?
Remember film sticks to itself and doesn't develop so you need a spiral to keep them separated or you'll have a lot if undeveloped spots.
Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk