The red RTV prevents vibration and thus reduces wearing of the spring ends. The safety wire is to keep the spring from flying around in the engine compartment should one come loose. The safety wire needs to be loose so the springs can do their job and let the joint flex.
My home made tools work fine. The large factory made one I bought When I first installed my exhaust incorrectly with too much angle in the joint making a couple springs stretch too far. It is correct now as shown in the photo. https://www.denniskirk.com/parts-unl...prd/283491.sku