Could be a radiator scaling up. Might be very early signs.
When I have had a radiator that had become clogged or scaled up, the typical symptom was running hot at highway speed (gauge at 3/4 or so), but not overheating and then dropping to normal (about 1/3 or so) when idling in traffic. A new radiator and fresh coolant cured the issue. This happened on both Acclaims I had ('90 &'92). The '90 did have some fins missing or corroded. I don't recall any fins missing on the '92 when its radiator was replaced, but that was long ago - my memory is somewhat hazy on that.
I'm assuming it is the original radiator. Correct? If it is, it certainly wouldn't hurt to replace it since you just replaced the HG and the vehicle has nearly 200K. I wouldn't want to redo the HG just because of an overheating issue that could have been prevented.
When I have had a radiator that had become clogged or scaled up, the typical symptom was running hot at highway speed (gauge at 3/4 or so), but not overheating and then dropping to normal (about 1/3 or so) when idling in traffic. A new radiator and fresh coolant cured the issue. This happened on both Acclaims I had ('90 &'92). The '90 did have some fins missing or corroded. I don't recall any fins missing on the '92 when its radiator was replaced, but that was long ago - my memory is somewhat hazy on that.
I'm assuming it is the original radiator. Correct? If it is, it certainly wouldn't hurt to replace it since you just replaced the HG and the vehicle has nearly 200K. I wouldn't want to redo the HG just because of an overheating issue that could have been prevented.