The glue that came with my kit was useless. Some generic brand that might be OK with some fabric, but was awful for me. It may as well have been hairspray. Prep was perfect, there was not one speck of foam on the board. The one can that net folks had reported using was not even close. The 3M products are the way to go. I wanted the 3M 38808, but needed it same day and opted for 3M #80 (which states on the can -for use on headliners. (high heat is the thing)) I bought 4 cans at $14 from home depot and used 2 & 1/4 cans. Two cans might work for you. It worked very well, but I got some bleed through. Surprisingly, rubbing alcohol worked the best to remove the glue from my fingers, so the stray bad spots were lessened with alcohol. And, I had started from the back of the wagon, so the spots are back there, and we don't look up much.
Still turned out OK and about 1/2 price of a shop. Would do again if needed (wagons much easier to remove the board) but wishing not to have to. It took several hours adding everything up -with the swatches, phone calls, extra glue trip, & aggravation, maybe the shop is OK -will never know
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'97 855na, Mobil 1, K&N, various IPD's and eBay's