The new seat side channels (yep the US$31.42 ones) have 3/8" diameter holes for the 5/16" locking pins which would make the seat very loose in the track. My factory built aircraft has 5/16" holes in this position so I think that is correct. Only 1 of the "seat belt plates" has a 5/16" hole, the others are 3/8" so I have produced 1.6mm thick doublers for them so that all of the pins will be supported in a 5/16" hole as they exit the seat frame. Other adjustments required were the shortening of the cross channels as the bend radius of the new side channels does not allow them to fit properly. Lots of work for what should be a simple assembly.
