Looking for a little help here. I have this G&B which I'm going to start on to do a rusto. I was trying to get some info on it for one reason I need to find a cylinder for it. The one I got with it is like 1/4" to 3//8" too wide, figures. Looking at the ID plate confused me (doesn't take much) it reads style 177 and model 1? Also the serial number isn't listed in Neils blue book. Last question is, is this really a 177? According to Jack's book he listed the 177 as a ten gallon and the 176 as a 5 gallon but this pump looks more like the 177 with bolts connecting the skins to the cylinder base like the 177? Any thoughts would greatly be appreciated, thanks!

I checked my Gilbarco book and it says that the T-177 came in both a 5 gallon and a 10 gallon version

The picture in the book matches yours!

Thanks Jerry, appreciate the input. Was confused by the style being listed as 177 and model being 1.