SNES internal hardware changes (older vs. newer models)?

[Greg2600]

My original SNES, now around 15 years old, has gone totally to the Yellow side. So I got another one, which is still a nice gray. I opened both up, and see that the older one has a ton more metal in there, and a slightly different board. Which is why it was twice as heavy. Very little information on what all that metal did. Anyone what Nintendo had all of it for? Are they heatsinks, perhaps that's why the old SNES's went yellow (from that heat disappation)? I'm wondering if I should but the old SNES's guts into the newer case, because the newer one's cartridge slot looks beat up in where the pins are.

http://home.comcast.net/~grizz4/ebay/P1010006.jpg

[Cambot]

I'm not sure about the differences, and compatibility between generations, but I'm sure the change had to do with cost-cuttting. As for the color, it seemed to have more to do with the chemicals in the plastic they used. I have seem some systems which were half yellow/half gray, apparently using two different "batches" of case housing.

[Greg2600]

Actually, after more inspection, there is one screw column on the base which is much higher on the new version. In order to have the old hardware fit in the newer base, that column would have to be cut lower, or the metal would have to be twisted or cut. That is not possible, because that screw is one that goes through the SHVC-SOUND sound board attachment. So the plastic would have to be cut down (good luck).

So a warning to all, should you want to replace your old yellow SNES, it's not as easy with a newer version, unless you have working hardware in the newer, making the old one expendable completely.