The instructions tell you to put the droop stop shims in the chassis when starting the assembly of the drive train, although they are a nice tight fit in the recesses on the chassis I found that while assembling the bulkhead that they fell out. So I left them to re-fit at the same time as the wishbones to save losing them. Another option would possibly be to hold them in place with a small drop of thread lock just to hold them in place but not permanent so that they can be replaced when needed. The assembly of the rest of the drive train installing the bulk heads and diff and spool went very smoothly, the roll height spacer pins on the bulkheads and motor mount make lining these up easy. But be careful when fitting the rear diff and front spool that you get the belt tensioner’s equal as there is plenty of adjustment on these more than on other cars I have built in the past, on my car the suggested position seems to be good for the belt tension with the belts not being too tight or loose. The top deck then just bolts straight on with no issues, as with the Xray it has a few options for what screws you use to alter the stiffness of the chassis.
Fitting the front wishbones and steering arms is very easy as the suspension pins slide nicely into the holes without need for any adjustment although when fitting the steering arms into the castor blocks they seem a little on the tight side but once the unit is fitted into the car this becomes very smooth and free.
Fitting the rear wishbones and uprights is just as easy the whole process of fitting these took me only a few minutes including building the turn buckles.