Astro Spectra Control Head Parts

[USPSS]

I just got 2 astro spectra with w7 heads and they the fronts look like they survived WWIII, these are remote mount units. Does anyone know the PART #'s of the parts needed for changout, the buttons I have tons of from my old A7 and A4 spectra, but I need the front cover andI think the lens if it is separate, I have never changed one and cannot find the changeout or take apart in the spectra manual, is it difficult? Also these radio's came from TN state surplus and they work great and cost $50.00 ea. now that is a bargain I could not pass up.

Thanks
Stan