How many different types of factory battery covers were there?

I've seen the type that looks like a "T" or is "T" shaped.

Is this also a factory battery cover:

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...item=4634204107


Or is this:

There were only two as far as I know. The earlier "T" shaped cover and the later box-style shown in the photo. There are the two covers described in recalls 9J and HO. The HO recall includes the yellow label as shown in the photo you posted. Recall info and the parts numbers can be found on my 'collectibles' webpage at the link in my signature block.

I am not sure that the cover in the ebay ad is an actaul HO cover...it doesn't have the notches for the batteyr cables as does the one in your photo.