Open vpn for remote access behine private wan ip

[mafiosa]

wan ip 172.16.34.254/26
my isp is wide spread and provides every customer with a staic ip from 172.16.0.0/20 and 10.0.0.0/24 with inter subnet access.I want to configure openvpn remote access within this network!!! Is it possible? If yes please help me out.I only want to access from these private ip series.But only via vpn.