OK, I have finally had time to refresh my 5.3 by changing all the seals and gaskets along with new sensors, do my BTR Truck stage 2 cam swap and also give my 5.3 a good cleaning inside and out. I also had PRC do some porting and machine the 243 heads down to 63cc chambers to go with my Cometic 3.910 bore .045 thickness head gaskets to bump the static compression to 10.5:1 and DCR to 8.5:1. I am replacing every gasket, seal and sensor on the engine, All OEM stuff. Now I know all gaskets and seals go on dry and should not using any type of sealant on them. What type fo RTV or sealant are you guys using when putting on the front and rear timing covers, around the corners where it meets the block/oil pan. I have the Sac City Corvette alignment tools for the front and rear covers so that will make life a heck of a lot easier. Just wondering what you guys perfer, I have been told RTV black and grey, does it really matter?