Well, today I bit the bullet and tackled removal of the LEXUS and IS 300 badges from my boot.
Step 1. Apply heat - CAREFULLY, I found around 150C worked the best, without producing any noticeable effect on the paint or badge.
Step 2. Slide floss behind badge to cut glue. I'm sure fishing line would have broken less, but I wanted to minimise any possible risk to the paintwork by using something softer. This worked about 0.5 letters at a time, before a reheat from the heat gun.
Step 3. Apply lots of glue solvent (I used Goof Off, which I found at Bunnings). At least 2 layers of a soft cloth, and a fingernail to appply a bit more pressure, worked OK, but very slowly.
Step 4. Clay Bar to remove the outlines of the badges. This was my first attempt at Clay Bar, and it is amazing. You have to get really close up, on an angle, to make out where the badges might have been.
Looks tidy, I think.
I thought I had embedding images into posts sorted, but it didn't want to do it, so have attached images.