Can I just hook up the ribbon
cables, not mount the entire sled, remove the blob, unhook the cables,
then mount. Or can u not unhook the cables once the blob is removed?

thnx again

It's best, but not absolutely necessary to unsolder the protective solder
pads while they're plugged into the circuit. (The player of course is
unplugged from the wall!)
Ideally, if you need to unplug the flat cables, the solder pads should be
resoldered.

Some players are not designed quite so intelligently, and the solder must be
removed prior to installing the pickup.
A anti-static strap comes in handy for this. It's another technician aid -
most of us have one but don't use it that often.

Mark Z.