When you say Alternative to electric driven fuel tap, is that what it is?
I thought the solenoid was part of the fuel shut off system. The fuel pump which is electric driven is elsewhere. i may be wrong, but i think the fuel tap doesn't include the pump, they are separate.
(its just the terminology you're using may be throwing me, a solenoid being just a type of switch, whereas driven implies a motor)
Removing the existing shut off valve and tap and simply replacing it with a gravity tap, is probably not difficult.
But is there enough room to get at it?
You may have to consider that If you disconnect the solenoid you may get a fault code on the ECU, so you may have that to contend with.
Can you not repair the solenoid?
I found a vid on youtube which may be of some help....
https://youtu.be/ZldV4FHF2n4