I took the mats out of my Impala because as Phil says they held in moisture and I don't know what material was used on that trunk. On my Bel Air I used a petroleam base material that does not require a clear coat like the water base Zoletone. I also chose not to use the mats but have white towels in place of the mats with no issues.
Did you steal the white towels from a hotel on the way back from Great Bend (409 sign)
On a serious note Dan, can you give me the details of what paint color etc you used on your 61 interior (dash, Wheel etc)
Steve