Just did some research and found out the top is a woven PVC material. I use the vinyl kit, probably gentler on the top since cloth tops can tend to stain easier. 303 may have also added chemicals that help can help keep the PVC soft and pliable.
Don't know if the one for tonneau covers would be good or not. This type of cover is made of a sheet vinyl. Wouldn't want to seal up the weaves on the roadster's top.
BTW the only stupid question IS the one not asked.
A Hui Hou
Read it and weep....the top is made of CANVAS and not vinyl.
You got served.