I used the reflectex under my hood. It seems to work pretty good if you can find a glue that will stick to it. I had to re-stick it with 3M tape after it fell down the first time. It hasn't fallen again....yet.
'64 swb stepside (gone) '57 1 ton '53 phone truck '59 swb '46 1 1/2 ton '68 swb gmc
