Given machine shop access, you can do whatever you want. It's not going to bolt straight up...the pivot point and the shock mount are different. It would likely be cheaper and easier to buy a '94 F2 in the first place.
Besides the fact that the really the biggest tire your going to get on a 94F2 swingarm that is going to give you any gains is a 170. You can put a 160 on a 90 rear rim and swingarm just fine. If he's so wound up about having a wider tire then tell him to save his money on buying and modifying this kinda stuff and go buy a newer bike.
Well I surely wouldn't recommend putting a 180 tire on a F2 or F3 wheel. For one thing you are decreasing your contact patch, your not gaining any performance by doing this none at all, well except looks I suppose. I agree also with Nominal...I'm a machinest, and have put a 98 GSXR swingarm and a 1100 rear rim inside of that, and 96 front forks and wheel, and a 97 subframe on a 87 GSXR. So yah with the right tools and machines you can make just about anything work. Now putting a different rim in a different swingarm you have to put different wheel bearing spacers in, and your going to have to look at how much further out does the sprocket carrier set out from where the counter sprocket is located.