Need advice on frame connectors

Johnny Dart said

It is imperitive that the engine and trans are in the car.The car should be fully weighted before you install them. It is also important for the car to be level when you weld them in.Ramps on level ground is ok,but the best would be on a drive on lift.

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This method doesnt make sense to me but i may be missing something. Isnt the point of the subframe connectors to counteract chassis flex. If all the weight of the car is on the wheels you are technically flexing the chassis. You need to get all the forces acting on the car neutral and the car level. If the chassis is loaded then it wouldnt be straight when welded together.