Read
this thread on the other board. I was thinking the same as you, but decided it's too much work. I'm going turbo now...
Short story -
The Silvertop bottom end is the same as the ZE with different pistons.
The ST block doesn't have the holes to mount the supercharger brackets.
A small turbo (GT25 or GT28) will get you more power than a SC, with less headaches and negligible lag.
A supercharger may or may not be cheaper than a turbo - depends on the super and the turbo.
No matter what it's a lot of work.