[ARC5] Plastic windows on SCR-274n and ATA

[J. Forster]

> Always wondered if they used different plastics for different batches. Maybe
> the mix was wrong? This is one of those times when a parts donor is
> handy. A few dollars spent for an otherwise-butchered set can yield a
> replacement window and loads of other goodies.

I'm pretty sure there are two different plastics. The ones that are in good shape are plexiglass. IMO, these would be easy parts to replicate.

-John