Manual steering box OIL or GREASE ?

went to check the fluid level on my 65 Formula S manual steering gear box and found it was filled with grease not 90 weight oil.
What is recomended for lube ? forgot to mention this car sat for 20 years . I've never seen gear lube turn to thick grease.
Mine was leaking and I filled it with grease 2 years ago and it's been fine