I agree with Geoff. I also use the VHT paint from the autoparts store. Strip all the paint and put on a fresh coat. I did this on a hot day as well, letting the piece heat up in the sun before painting a fairly thick coat, then coming back in a couple hours to check.
If its dry to he touch, bring it in out of the sun and allow it to cool down to room temp before handling, and even then be careful. You get the best results if the entire piece is allowed to heat up evenly before you spray. Don't rush things.
Don't need anything fancy, I just use the empty trash cans turned upside down as a spray table.
Not a close-up, but here is how I received it, with chips and gouges....
...and here is how it turned out.