A manual can make almost any car fun, at the expense of the clutch that is. You're friend is nuts for doing the swap. Only a maniac who really enjoyed his car (or was broke and had a lot of time) would do a swap like that!
You know, when I read " he sold it" i just shook my head, but replaced with a 66 Mustang! I remember there being a 66 1/2 mustang too. Not sure what the deal is, but if I could afford it, I would daily drive a classic mustang.
Haha, he was a professional drifter in our country, and had a lot of free time, so it's what made him happy I guess :) He did the swap in his garage, and it actually seemed pretty easy. Only downside is the dash still had the PRND markings.
I did a full photoshoot on it a while ago (pre-gearbox swap), you can check it out here if you fancy: https://steemit.com/photography/@garethb/searching-for-silvia-shooting-the-nissan-s15-original-work