UNDERCOATING SUGGESTIONS

I am wondering if anyone has used this 3M product and can give any pointers. I don't have a rotisserie, and I am nowhere near complete with prep, only have aprons close. The guy at Wessco said this product has a great shelf life. I'm also wondering about shooting the product, I don't have water traps and am wondering if I really need them for this stuff?
The questions I have are basically process, questions. Should the whole underside be shot at once? Any tips for doing this with tall jack stands? Any and all comments would be appreciated, from PPE, ventilation, etc. Thanks in advance!

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