I put washers on everything.
Put washers on the studs for the motor, that way the nuts don't eat down into the block.
The number of washers will depend on what chassis you have. I have a triton and their is a total of eight washers on each spindle that's used for adjusting cross and one washer that goes above the helm and under the castellated nut.What about the spindles and anything with a bearing and a heim????