The 486 slc is not like a full 486DX however.
If I remember the 486 slc is basically a 386sx with 486 instruction set and not the other architectural optimizations
As it's a cyric chip and not an intel one, the architecture is going to be different.
http://en.wikipedia.org/wiki/Cyrix_Cx486SLC I wouldn't bother risking damage to the board for the amount of speed increase you'll get. It's more of a collectors piece & should be kept as close to original condition as possible.
I'd love to see someone build a modern bridgeboard though. You'd want to have a graphics chip on there as well, but you could rtg to it using similar tech to the siamese system.
