brushing upside down

[slo]

I have a show vehicle that does not need to be removed off the frame and I want to know if I apply this upsidedown are there any set backs? Or if anyone had any problems applying it this way. I have other products that will work but I would like to use KBS on this restoration. Will it not flow out correctly? Do I need to thin it out etc. Any input would be apreciated.