Boxerworks.com

Get a short spring the right size and add an extension of steel wire to make it fit.

Brilliant, Jean.

Since we're on the subject, I've had recurring problems with the CS springs popping off the tang on the CS itself. Even when they're on, there's a smidge of play on the CS end. Is that normal? And am I even putting them on right, hooking them on from under? It's near impossible (for me) to switch it around given the limited space to to fit the other side through the lobe on the engine. Am I doing it wrong?

I had trouble like that with OEM springs. It seemed to me that the hooks were not formed correctly.
I use "homemade" springs like I mentioned, with keepers fashioned onto the frame end, too.