I just cut it open like normal with an angle grinder, mask, eyes and ear protections and gloves, went like butter. I cut the bottom out and use both of mine as bottom drain vessles. I went all electric as well. Everything else is still coated in rubber and seems to work great, the maiden voyage was last weekend so I still have tweaking to do.
From what I have seen on my kegs and other threads on the subject the handles are not stainless under the rubber so if you remove all of it you'll be left with an egg shaped vessle, which could be really cool depending on your design and skill level.
Good Luck.