Are barrel connectors ok to use to splice 2 sets of 4 guage power wire together? I have alot (pre cut) and want to change my 8 to 4 cause the 4 is starting to melt cause its close to the exhaust I guess. The cables going in the firewall on the pass. side in factory grommet an is still getting burned, any ideas? Is the barrel ok to lay on the floor or should it be insulated? Im still new to all this so any help will be appreciated. Sorry for 2 questions at once, Thanks for any help.