Oh my, you are really getting down to the Nitty Gritty with everything. 30 rear wheel horsepower would be awesome on a GZ. You would be able to frighten a lot of bigger bikes due to the power to weight ratio.
A GZ with a blower! It must have had a bucket full of mods to even run properly. Sounds like a short life engine if opened up on a regular basis. But what the h**l, it was likely a different way to get where you want to be with the GZ without a large cost.
I find these projects very fascinating. They are works of art in some cases and deserve to be appreciated for their effort and planning.