The 180B SSS we got was hardly tuned, the main difference was the dash, the dogleg patterned gearbox and twin SU's, and a tacho in the dash. It didn't make much difference, if any to the performance.
They were a huge step backwards from the 510 and as the 610 weren't really a replacement as they were a bigger car and marketed as such. The replacement for the 1600, in terms of size and marketing out here was the stanza, which if we got the JDM spec with the IRS and the coupe, would have been a good thing. As it was the Stanza was a pretty good track car, you can make the solid rear end work much better than IRS on a smooth surface like a race track.
The 180B was, and is a very ordinary car. However, they were good rally cars because they were cheap, the coupe was strong, if heavy, and Group G rules and to a lesser extend PRC rules allowed a lot of freedoms to get the most out of the engines. For street sedans, or basically production touring cars that I ran, the rules were very limited for modifications, and as a result I ended up running near 1000lb springs in the back to keep the bum on the ground, and couldn't run a camber kit to fix the problem of excessive negative camber on the rear end when lowered because of the rules. For a rally car where you didn't run it as low the trailing arm suspension wasn't a handicap.
The 180B also misses the classic car love, unless you are a hipster with tight skinny leg jeans, a bad beard and top knot driving a shitbox to be ironic.
The import costs to the US would be worth more than the car, and then the thing would rust away to nothing on the boat ride over, they rust worse than a Zed......