Hi, Albert, welcome to the bucket, nice additions.
I am going to tell a curious (and somewhat funny) event with a drawing similar to your BTR-60/PT-76. Several years ago, a pal from a spanish military forum (user name Sahureka) was explaining the feasibility of this kind of vehicle and he upload a drawing and a picture with Photoshop ( but as you can suppose, nothing was real, just a drawing and a fake photograph). Last year, tying to find data about an hybrid cuban MRAP, I found Sahureka's drawing in the web, even with a "real life" name! (BTR-60 M1961/1 )
P. S. I will try to find booth the drawing and the picture!