I have some of those square cable clips you use zip ties through. They need to be stuck to the inside of the nose of the car so rivets are a no go, and the adhesive pads are useless.

Is there a tried an tested method/glue/etc to getting these stuck on securely? or is there a better way of doing it?

Tiger seal or fibreglass from inside

Araldite 5 min epoxy works well.

Abrade, degrease and bond - There's no removing them though!

+1 for tiger seal
I remove the sticky pad with a Stanley knife. Put some tiger seal on and they are still stuck in place

Something like this to replace the square tabs to be really secure?
http://www.bighead.co.uk/english/products/standardbigheads.html

[Edited on 18-8-15 by loggyboy]