vanisleboy

I am replacing the seals on my differential. 1979 280zx Non-Turbo Coupe. It appears I have a R180 Differential as the connection to the differential from the axle is one large rod with a geared end and not the 4 bolt flange. I thought I ordered the side seals correctly but they look minimally larger than the cavity to be pressed in. Are the seals different on the 180 and 200? Or will these go in once I start pressing them in? Thanks for your help