F28 battery question?

My 72 Swinger 340 Special was coded F28 for the battery on my and my buddy Joel's broadcast sheets, from what I've been able to find on the web is this was a heavy duty 500amp battery, I'm looking to order a reproduction battery but I haven't been able to find out what this battery for 1972 looked like, green cap or yellow cap or red cap? These battery's a pretty pricey and even more so to get all the way up here so I'd like to get this right the first time so any knowledge anyone can share would be much appreciated.

Dan