I need some help from the board family. I had a death in the family and I'm the new owner of a small winchester collection. I'm having a little trouble finding out what model my Model 61 is. It is a round barrel but I'm not sure if it's the grooved receiver model. I'm more of a pistol guy, so I'm not well versed in what to look for. Are there markings on the receiver or serial number runs that the grooved receiver model was made in. There is also a model 63 that I'm trying to find out the same issue. I'm picking up the guns this weekend so I was wanting to get a jump start before hand. Any help would be great. Thanks...