For older specific revisions like R45, the 4PDA BiTGApps Thread often maintains an archive of various builds including R45. Key Features of the R45 Build
At roughly 70MB to 90MB , it is ideal for devices with small system partitions. bitgappsarm1200r45 link
Automatically applies battery optimization for all Google apps and services. For older specific revisions like R45, the 4PDA
Can be installed as a Magisk module if you prefer a non-destructive installation. How to Install BiTGApps R45 For older specific revisions like R45