The 2 small plugs in the Trunk between the Shock plugs

[fc7cuda]

Looks like these are available here:
http://www.rtspecialties.net/proddetail.asp?prod=2027031

[Shane Kelley]

Yup,    They can be a bit hard to get installed.  Any lubricant will help a lot.  I use a rubber conditioner that helps them push in and maybe even helps them last a little longer.

On a 70 those plugs are the heavy rubber 1" plugs...  They can be tough to install... Sometimes a like simple green & push in the center of the plug with a 3/8" extension....

I started using WD40 to install them. That makes them go in pretty good. They are buggers to get in dry. I have a little Snap-on stubby 3/8 ratchet with a ball shape on the end of the handle that I use to install them.