Help with prepping Urethane Rear Spoiler (pics)

[RedXray]

Found a good deal on a new (open box) Street Scene Spoiler for my GMC Sierra. The instructions say to scuff, wax & grease, prime with PCL 905 primer (2K) etc. The spoilers primer looks rough on one side like it has gouges. It doesn't mention anything about adpro but I did the float test and the piece indeed floats. I'm thinking maybe 220 DA to smooth out the rough primer, adhesion promoter, SPI 2K primer 4:1:1 (I'm out of epoxy), activated DBU base, UV clear. You guys see any problem with prepping this poly urethane part as described?

 

[Barry]

Is it fiberglass or urethane? if glass, just 2k or epoxy and go, if a urethane that floats, adpro and go.
Reason i say use adpro is it looks like you will be at the sub-straight once you feather out the chips, if its a urethane.
I have no experience with this part to know what it is.

 

[RedXray]

Barry the paint sheet says it's Poly Urethane. I can't find any ID markings on the inside, but yeah the test piece did float. It looks to me that someone tried to prep one side as it has scuff marks on only that side. What concerns me Is this rough side has these shiny blotches. I'd like to spray a reduced coat of 2K after adpro as a visual guide then wet sand with 400 and go with the base. This is a flexible rubbery piece I'm working with.

Here are the splotchy/shiny looking circles. I can't tell if it's manufacturing or someone has sanded or scuffed through the factory primer. Could those blotches be a release agent?

 

[Jim C]

i am always leary about the primer these aftermarket companies use on the fiberglass and urethane parts. very rarely do i ever get something that has a catalyzed primer on it. take a rag with some acetone or gun cleaner and wipe the primer in a spot. if the primer melts and wipes off then remove it all with some acetone and rags. once off use adpro and reprime. if you wipe and it holds up then your lucky. spot in some adpro on any bare areas and prime again as necessary.

 

[RedXray]

i am always leary about the primer these aftermarket companies use on the fiberglass and urethane parts. very rarely do i ever get something that has a catalyzed primer on it. take a rag with some acetone or gun cleaner and wipe the primer in a spot. if the primer melts and wipes off then remove it all with some acetone and rags. once off use adpro and reprime. if you wipe and it holds up then your lucky. spot in some adpro on any bare areas and prime again as necessary.

I did a wipe with lacquer thinner and I wasn't able to remove any primer.
I'll update after I get the base and clear shot

Thanks for the reply.