Sounds like a sound plan. The Motive should work great for both vehicles - I use mine on the BMW & Subaru.Thank you for the great information everyone! It really helped my decisions here. The Real OEM site was super helpful as well. I ended up passing on the FCP kit. I was on the fence, then the kit became unavailable due to the lower radiator hose being backordered with no ETA, so between that and the feedback here it kind of sealed the deal. I ordered this hose from the local BMW dealer instead to the tune of ~ $68!
This is what I went with from FCP: a new water pump (metal impeller Hepu), thermostat, upper radiator hose, BMW expansion tank, new cap, expansion tank hose, fan clutch and blade, coolant level sensor and the BMW coolant. I noticed I already have an aluminum thermostat housing installed, so I just ordered a new gasket. All of these were either BMW parts or listed as "OE." I decided to buy all new nuts and bolts for the water pump, thermostat housing, and fan clutch since they were all quite cheap.
I decided to hold off on replacing the hoses that went to the throttle body and heater core because it looked like the job required removing the intake manifold and they still seemed in fair condition. Hopefully I won't regret this! I also passed on the clamps because the current ones appear to be original but still in good shape.
To echo Craig in Canada's comment about these engines running at different temps - there seems to be two common thermostats for E36s. The Mahle one in the FCP kit is actually listed as not for any 328 after MY1996. It looks like for some reason BMW went from an 88 degree to 92 degree thermostat mid model. I doubt it makes much of a difference, but I went with a 92 degree BorgWarner thermostat to follow what was spec'd.
Independent from the cooling parts - it's also due for front and rear brakes, so I went with Zimmermann rotors and Textar (listed as the OE supplier for BMW) pads. I picked up the Motive European Power Bleeder kit to aid in getting some fresh brake fluid in the system. I'm hoping this (with the appropriate adapter?) will work with my Accord as well.
I was going to ask if the vanos seals have been replaced but being a '98 it might be a single vanos and not apply (I have a '99 528 which I believe was the first MY they put the M52TU in the 5's).