No, the PM8G that is used for a metal gasket retrofit for a PM800 Series can not be used for the PM700 Series.
The PM700 Series doesn't have the rounded groove like the PM800 series does for the remote or integrated displays. The only way the PM700 series can be mounted is by using a 3.62 inch by 3.62 inch cutout. For more information refer to the PM700 Installation Manual.
Thus, a PM700 Series cannot replace a traditional analog meter.