FLM Parts Not Fitting?

[RC Nut]

I have the 3905 Extended Chassis and Hybrid Bulks.

The chassis does not fit flush with the bulks is this normal? The grove where the two meet is not wide enough.

The stock shock towers do not fit the hybrid bulks. I have ordered FLM shock towers they look to be thiner than the stock ones so they should fit.

The Hybrid Bulks only came with lower hinge pins what pins do you use for the uppers? The stock pins will not fit through the FLM chassis.