if you go slow you can notch out for the para nose cover with a dremil. i did these 2 or you can send it off and for $50 each get someone to mill the receiver out for the nose. i chose to use the dremil on mine.
the regular rear site can be used if you modify the rear block. just grind slow to remove enough metal for the site bases to fit. i chose to do this on mine.
this was done on some rifles in some countries or you can buy the para sites for around $60.
watch the different for sale sites and you can buy the parts to do all the conversions.
i finally finished 2 of mine last week. i have been working on them for a few years.
2 more to go, still gathering up parts.
(these are a mix-master of parts left over from other builds. )
both are 922r compliant.
1 has a 16-1/2" barrel (israel hand guards) the other is a 18" barrel.
they shoot good.
good luck with your build.