You will need to get a used 922 or maybe even a 905 that was already authorized for digital, if you do not have problems with brown outs or bad power you should be ok, you can setup a 90cm dish on Galaxy-4R and SRL will be able to activate your programming on X4-430, you may need to set the feed to rotate 90 deg to make it work.
If the 4dtv is new you will need a buddy with C-band to authorize the unit for digital on C-band, a 920 will lose this after a master reset a 922 will not, the 905 should be like the 922 so you should be good to go.