My drivers seat has a sunken pad and/or springs, and its seatback has a broken spring that's sprung facing Forward ('86 300E). So I bought an entire drivers seat (frame and all), from someone over the phone parting out a '90 300E. My original thought was to have someone do a straight swap w/it, replacing my entire existing seat w/the one from the '90.

But the parting out owner cut the bundle of approx a dozen wires at about 8" long from the bottom of the seat frame. I can see some backache or labor hours coming there... That bundle is wrapped up in some not very factory-looking fabric tape, don't know if that could be a sign of anything or not. And the back panel of its seatback is a different style than the originals in my '86, which have the shell w/web pocket back there; this replacement one has an upholstery pocket - is that what originally came on the '90 w/MB-Tex? I'm really hoping someone doesn't tell me this came from an earlier body style car.

Considering that I know everything electric on my existing seat does work, incl memory, what would be the best way to swap needed parts, leaving me w/good drivers pads and springs, and matching the look of the pasenger seat? I'll be paying hourly either a mechanic or auto upholsterer for this job, to save my achin' neck. What's the most time-efficient way to get me best seated here?

These are all Blk MB-Tex, so nothing great about having more of that facing the rear passengers. And I want both seat backs to match. I'd prefer to keep my 2 original seatbacks, I like that look better. My existing drivers back shell is on Tight, btw. I've taken out the 2 screws at bottom, and can't get it to budge, even when prying w/a thin tool.

I'm also thinking that if the covers on my original seat are going to be removed and replaced, then I'd order one of those aftermarket seat heaters and have that installed too, while they're at it. Like this one: http://v12uberalles.com/power_head_rest.htm