Just replaced my heatercore-some thoughts.

[Iroll_]

1) remove the carpet on the drivers side...It's easy to do and saves you the hassle of trying to catch coolant and make sure to set both heater positions to full hot.
2) slide the white portion of the brake switch forward to remove it...This was tricky for me to figure out.
3) put some towels in the footwell to act as a pillow...You'll be contorting in bizarre ways. Having a soft place to put your head helps.
4) When installing the heater core...gentle finesse in inserting into its home while making sure the heater core pipes are out of the way ( I bent mine a bit).
5) insert the horse shoe clamp on the top hose before the bottom clamp.
6) procure an extra set of horse shoe clamps...it's tough not to bend them.

My original Behr unit didn't appear to be bad...Looks like it was just the O-rings.
Since I had the heater core ( from Swedish Car Parts/lamps on eBay), I figured replacing the unit as a preventive measure wouldn't hurt...Though I saw no evidence of the core it's self leaking, just the o rings had residue.
Note: The aforementioned eBay seller has a reputation on the 850 forums for making an improved heatercore (crimped and vacume formed) where as the Original unit is just vacume formed.
Preliminary results indicate that the eBay heatercore is working as the original...as far as heat output goes.The O-rings that come with th eBay heater core ( includes 4-nice touch) are made from Viton...Very durable.

Will update as the miles add up.

[Antherzoll]

I'd assume you'd need to do this from the drivers side? I'd remove the drivers seat just to make the job easier. Isn't that hard to to. 4 bolts, quick release for the belt, and the electrical connection under the seat. Just make sure the seat is in a good position (upright) to aid maneuvering it out the door and do not switch on the vehicle until the seat is back in.

[Xheart]

1) remove the carpet on the drivers side...It's easy to do and saves you the hassle of trying to catch coolant and make sure to set both heater positions to full hot.
2) slide the white portion of the brake switch forward to remove it...This was tricky for me to figure out.
3) put some towels in the footwell to act as a pillow...You'll be contorting in bizarre ways. Having a soft place to put your head helps.
4) When installing the heater core...gentle finesse in inserting into its home while making sure the heater core pipes are out of the way ( I bent mine a bit).
5) insert the horse shoe clamp on the top hose before the bottom clamp.
6) procure an extra set of horse shoe clamps...it's tough not to bend them.

My original Behr unit didn't appear to be bad...Looks like it was just the O-rings.
Since I had the heater core ( from Swedish Car Parts/lamps on eBay), I figured replacing the unit as a preventive measure wouldn't hurt...Though I saw no evidence of the core it's self leaking, just the o rings had residue.
Note: The aforementioned eBay seller has a reputation on the 850 forums for making an improved heatercore (crimped and vacume formed) where as the Original unit is just vacume formed.
Preliminary results indicate that the eBay heatercore is working as the original...as far as heat output goes.The O-rings that come with th eBay heater core ( includes 4-nice touch) are made from Viton...Very durable.

Will update as the miles add up.

An extremely painful job for a first timer.

Before connecting pipes, it is an easier struggle if the pipes were unrouted at the track/fastener above.
Once connected, and horse shoe pin secured in place, push the pipe back into track/fastener -- lubricate for ease.

It is OK to cuss frequently during this repair. This is PG-13 job.