Sikaflex canopy-to-aft-window gap

[Flying Scotsman]

Starting on the last major task, finishing up details on the canopy (front fairing, etc.). I used Sikaflex for both the canopy and the rear window, and now it's time to sand the aft edge of the canopy to get a nice fit with the rear window. As it is now, it's very tight, as in too tight, because I know if it gets hot it'll expand and likely not be openable.

What are you all using as a good gap between the two if you used the Sikaflex method for the canopy? I don't want a huuuuuuuge gap, but neither do I want it to get stuck so it can't be opened when things expand.

TIA!

Steve