I am replacing the floor mat (cutting it myself from a 6 foot by 3 foot piece of 1/8" thick mat material) in my 1966 GMC 5500 truck cab and need a shifter boot to finish the job. All I have now is a hole in the floorboard and what looks like the remains of a foam ring between the floorboard and the new process (my guess based on shift pattern) five-speed transmission. There is also a two-speed rear end cable (to vacuum switch) going through the same hole. Does anyone have a suggestion about what to get and where? All I can find are boots for the pickup truck four speed transmissions. The hole diameter is about 4 1/2 inches.

JRMunn