Frame off Restoration

I am doing a frame off restoration of my 74 TR6. Does anyone know the correct color to paint the underside of the floorboards and fenderwells?
Also what color should the front sway bay and skid plate be?
Thanks
bdavid

I also am doing frame off resto. I have a 73 TR6, when I removed the body and began to replace rust (lots of rust) the car was severly undercoated with an asphalt based undercoating (very hard to remove) under that was body color. It seems as though Triumph paints the car as a unit, therefore I have also painted mine as a unit (signal red) The chassis and susp parts are all black, and not a very high quality black at that. They parts are dipped from the factory so runs are everywhere. Eastwood has the closest chassis black (satin finsh) to the original that I've been able to find but there are not a lot of references other than the Vintage Triumph Regester
.http://i139.photobucket.com/albums/q294/cartoon14_2006/100_2759-1.jpg