I find it interesting that Westside decided to go with what appears to be a Q3 switching pilot instead of the Q4 slat pilot. They put the slats on the HO model but not the O. Also, the information I have gotten on the tenders is that the larger tender and water bottle were designed to go together. It's possible 4625 wasn't outfitted with these tenders. I'm still researching it before I get the model repaired (there was a fire in the coal bunker after a bad short). So I may modify this or try to pick up a normal Q4 tender.