+1 on the frame being a shogun.
+1 on the frame being nice and worth restoring.
+1 on the frame being made with tange tubes and forks.

the frame looks like a sport-touring frame. rear dropouts might be shimano. my 1985 shogun frame is a full touring frame but looks very similar to yours: same lugs, same fork crown, same tange dropouts. it has the same seat cluster, cable guides, and shifter bosses. the rear triangle is chrome plated underneath the factory paint. my frame is tange 2 seamless, and the fork has "tange 5c" stamped on the steerer tube. my fork is not chrome plated. right now my frame and fork are at the powdercoater's.