Meth line routing help
 

Going to be installing the BMS 2.3 trunk kit this week. I was going to run the line under the car, but decided not to. I am now investigating how to run it through the cabin. Have any e60 guys done this? I found DIY's for rear seat removal and all the lower trim removal. But there isnt any real DIY's for where to run the wire and tubing on the e60. Found lots of DIY's for E9X's, and it seems simple, but wanted to get some input from the E60 crowd.

Is it pretty straight forward where to run it out of the trunk and into the cabin, then again find a grommet to get it through the firewall into the engine bay?

I haven't done the meth kit, but the routing was super tight when I did my backup cam. Also finding a grommet through the firewall looks tough (look up routing USB cable for JB4) I doubt it's impossible. Meth line might get pinched or squeezed though when running it along the edge of the carpets.

I can't possibly understand why you think going through the cabin is somehow easier than going under the car.

I planned on under the car, but couldnt find an existing hole out of the trunk space that wasnt near the exhaust. I ran it through the interior yesterday, took about an hour, didnt have to get on the ground, didnt get dirty, didnt have to drill any holes. It worked out better than I thought it would.

But you also have water/methanol running though the interior of the car. Drilling a proper hole and getting under the car is but a minor annoyance in this sort of project I think. You might as well have just used the window washer tank.