Crowbar circuit fuse placement
Your circuit with F1 overlooks how a crowbar circuit is designed to operate--the SCR is intended to conduct a very large current, forcibly blowing the supply fuse and isolating your circuit from the overvoltage.
The idea of a crowbar circuit presumably takes its name from the act of throwing a metal crowbar onto a live circuit causing protection elements to blow, either accidentally or to prevent a more severe incident -- electrified trains often carry third-rail crowbars to short the supply in an emergency when time is of the essence.
If F1 is present and blows, then your crowbar circuit does nothing--F2 does not blow and the overvoltage is applied to the load. Instead, you should have F2 (only) and ensure that SCR1 can handle the full current needed to blow the fuse. According to its datasheet, SCR1 is intended to handle up to 0.415 A2s of I2t.
I don't know what fuse you are using, so you will need to consult your fuse's specs to determine what I2t is needed for it to blow. For example, this fuse will blow in 0.004 seconds at 10A, for an I2t of 0.4 A2s, which is quite close to the absolute maximum rating. You may want to consider a faster-blowing fuse than my example, a lower current, or a larger SCR.