Russ - the attachment is a good reference guide. It has now narrowed down my chassis frame to a M8R or a M8S or a M10S M series? Now, if I can find a definition for the differences between the 3 I will be able to finally figure out mine. I am inclined to suspect M8R or M8S for a 8 airbag system (which I have) but unsure about the R or S difference?Many Thanks!Bart from VA