Matt, the car you are thinking of is Jon's one, which is silver...
He bought it in Portugal and it's currently in Gibralta awaiting transport to the UK.
I had always assumed the 140Z/160Z to be a PB210 but it isn't. The Japanese 1600 Sunny Excellent coupe is a KGB210 and the 1400 a KHB210 so it seems logical for the Z to be the same.
In Nissan engine codes, a long wheelbase is usually denoted by a G prefix (as in GC110 vs C110) but it seem in the case of the B210 the G (or H) prefix denotes engine size instead. I checked the wheel bases in a Japanese Sunny Excellent brochure and a 120Y brochure and they look to be the same at 2340mm. I'd wager the revised frontal styling is still therev to add a little length to the engine bay to accomodate the L series though.
I'm not normally a big fan of B210's but I'd have that yellow 160Z in my collection like a shot! Most awesome
-Ed