OK, my final word ... JMHO FWIW ... Gripper is a great primer , but not as good a T2 for attaching canvas to foam ...
It doesn’t stick as well as the T2 ,even after a most Generous coating ..and I have a few places that have bubbled /detached from the foam under the canvas... Never had that problem with T2 ...

will try the iron trick and see if that works with the Gripper as well as T2 does... If not we’ll have to inject some glue under the canvas to try and reattach it ... That should be fun ...
For attaching canvas to foam ... T2 ... SI !!! Gripper ... NO !!!

I’ll finish the rest of the job with T2 ...
Drat!!! Now I’m wondering if T2 will stick to the Gripper ???
Cliff ... yes , time flies eh ???
Mary ... Glue !!!

It worked SUPER on my Foamie #1 and is still in great shape ... even living outside all this time ...
SJ, At least the T2 stuck ...