I would sugest always using a double roller timing chain in any application. Yes there are other advantages, but I beleive the main one is insurance. The stock type fiber gear sets are weak at best, and they do strip and break with frequency. They also wear out much sooner.
A double roller chain set will last the life of a quality built engine and I have never seen one fail for any reason. That in itself is a good enough reason to spend the extra cost considering that 2 sets of stock gears will wear out in the same amount of time. The other factor is that when a stock type set breaks, it can cost much more in breakage of other parts.
Even in a totaly stock overhaul, that is the one part that I will always upgrade if I build the engine.
As far as fitment goes, it is a direct replacement if for the proper application.
Hal
Love hard, drive fast, wear your seat belt.
PS, that's my 'bird...... My Mustang is too ugly to take pictures of yet........*G*.
http://www.teleport.com/~cosa/bird2.jpg