Thermal tape is on way, but you could also use super glue. Put some thermal compound on the GPU, but leave a small area alone in two oppposite corners. Put a small drop of super glue and attach it to the fan. That way, you'll have the benefits of thermal compound, and it's still properly secured
Get yourself some thermal grease, you probably already have some. Go get some superglue. Put a small coat of grease on the bottom of the Blorb, then put 3 small dabs of superglue on it and stick it on.