The two forends are totally different. The hole spacing is different on both, as is the barrel channel as the barrels are different diameters. In addition the Encore Frame is wider than a Contender or G2 Contender Frame and the ears of the forend that fit back over the Frame are also different dimansions.
I just kind of went through this as I was going to try to modify / fit an older Rynite Super 16 Contender Forend to an Encore and gave up on the idea.
Larry