As one who has no service lift (and I don't trust ramps) and has to change the oil laying flat on my back, I thought I'd pass on this trick for making re-installation of an S90 belly pan easier. Also works on a 940 (though you can change the 940 filter with the pan in place).

I got tired of trying to hold the pan up with one hand while fishing around for the bolt holes on the cross-member; same with the two screws on either side of the pan. The pan was made a bit over-sized, so I always had to force it to go where it needed to be.

So, I went to NAPA and bought some metric "step studs" that are 8mmx1.25 on one end and 10mm on the other end, with matching 10mm nuts. Ran the studs into the 8mm bolt holes on the cross-member ... and now I can pop the belly pan over the studs and allow the pressure of the pan on the studs to hold it in place while I install the nuts (and large washers).

For the side screws, I went to Lowes and got some "hanger bolts" that have sheet metal thread on one end and #10 machine thread on the other (take one of the screws from the car to Lowes to get the right size sheet metal thread. I installed the hanger bolts in the frame holes on the S90 and the belly pan slides right over them; then run nuts up onto the machine thread.

For the step studs, try to keep the 10mm end short, so they won't stick down too far and possibly get damaged by speed bumps, etc. Length of the hanger bolt machine thread is not critical, as it is surrounded by car frame.