Compile Error unstable library [E0658]

[RydalWater]

I seem to be having 0 luck figuring out the issue below while trying to follow a guide for the RaspiBolt installation of a new BTC Node. I've tried swapping to nightly, made sure I'm updated to latest stable or nightly.
rust version = 1.60.0 / nightly = 1.62.0
rustc version = 1.41.1
cargo version = 1.41.2
Pi OS = Raspbian aarch64

Apologies in advance if I am being dense.

[RydalWater]

Removed rust completely, did a fresh install to get back to rustc version 1.60.0. Followed the steps again only to find that executing the following command to build electrs (v0.9.6) installation appeared to lead to installation of rust 1.48.0.

cargo build --locked --release

Accessed the rust-toolchain file from the download (v0.9.6) using a text editor and modified it to read 1.60.0. This seemed to fix the older installation issue.

The result......SUCCESS!!