...man that was cold.I don't know if the 93 will fit, but you have to be the first man I've ever known that wanted a shorter petcock! I'm sorry, just couldn't resist.
Someone will see this and answer you question here sooner or later.
I'll go away now........
Ahhhhh, great info....That petcock is much bigger than on my bike. I have a 95, but the tank is identical to the first gen bikes. The petcock should be the same as well, and it definitely shouldn't be down that far.
PO might have changed it for whatever reason. Rebuild kits should match all years of EX. If it's a problem you might try an old petcock on ebay or a bike graveyard.
Does it happen to have a prime setting? This would be a dead giveaway it's not from an EX.