Im on a project to make exact replicas of these gloves. I have owned many pair of these and actually far inferior to the old Casanova's. This past year I have acquired both ols MM Las Dos and Casanova. The Casanova won hands down in what shape they were in. In the 80's my MM's leather was substandard but the leather MM's from ebay was in good shape but the liner was torn up and the foam crumbled.
After dissecting them here is what I found and something you should take into strong consideration. Foam is only good for the main area of the glove, the punching area. The wrist and cuff should be cotton batting anything but foam. Even Flores gloves never used foam in these areas. When foam gets repeatedly soaked with sweat and dries over time it gets very brittle and hard like stones.
Next is the welting. Welting is white, a thin strip of leather placed between the pieces of leather and sewn in to make the joint stronger. That is the old school "white line" you see going around the glove. I believe only Grant still does this. On the MM's this welting was a flimsy weak leather. On the old Casanova it was actually rawhide and as good as the day it was made.
On the Casanova the main foam area was brittle, stony so on the inside of the glove at the wrist joint i made a slit across and removed the old foam and replaced it with foam from some old Ringside Classics I had. Re-sewed it and the gloves are like new. The wrist area is like a vice when i tie them on. I can't savage the old MM's so I took them apart to make templates to make my own.