Set your gaps with the struts disconnected, and remove the striker pin from the bonnet, the stuts will naturally want to push the bonnet forward when closed, so set the bonnet about 3mm further back towards the windscreen, once happy with the gaps, and height of the bonnet, you can refit the striker pin, so that it drops straight through the centre of the bonnet lock...
I'd also replace the washers on the hinges for new stainless items. as the struts put them under a great deal of strain
Thom