Need tips for prepping a car for paint

[Mrfixit]

After many years and several other projects, I'm finally concentrating on prepping my 68 Camaro for paint. I've done a lot of panel replacement and several custom treatments but now it time to take it to the next step. I have a few questions and, I'm sure that I'll have several more before it's shiny so I'll say in advance: Thank you for your advice. Here are the latest questions:

(1) How do I remove all the caulking from the gutters? It appears that, before the car was repainted before that they added new caulking. There is so much caulk that the gutters are at least 1/2 full. I'd like to strip out the old caulk and add new. What removal method do you recommend? Should I just get a wire wheel on go at it with a grinder?

(2) I was on a E-Bodyshopsupplies.com and was looking at an epoxy primer called: Metallock DTM. It's a high-build sandable primer. Opinions? Recommendations?

Thanks again,