You'll get the 6.5" speakers in if you use some .5" MDF spacers in the original pods.
Remove the OEM speaker, place it on top of a sheet of MDF, draw around it with a pencil, mark the screw holes too. Cut along the line you've just made, drill clearance holes and counter bore them. Give it a quick paint, and screw it down to the pod with some sealant in between. Then screw the 6.5" speakers to the MDF.
Oh, I new there was a reason it wasn't so easy....You may need to split the spacers so they are .5" at the top and .25" at the bottom, or is it the other way around........